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- # Compiled by Charles Harris, dated October 3, 2002
- # updated to 2002 values by BasSw, 2006
- # Updated to 2006 values by Vincent Davis June 2010
- # Updated to 2014 values by Joseph Booker, 2015
- # Updated to 2018 values by Jakob Jakobson, 2019
- from __future__ import annotations
- """
- Fundamental Physical Constants
- ------------------------------
- These constants are taken from CODATA Recommended Values of the Fundamental
- Physical Constants 2018.
- Object
- ------
- physical_constants : dict
- A dictionary containing physical constants. Keys are the names of physical
- constants, values are tuples (value, units, precision).
- Functions
- ---------
- value(key):
- Returns the value of the physical constant(key).
- unit(key):
- Returns the units of the physical constant(key).
- precision(key):
- Returns the relative precision of the physical constant(key).
- find(sub):
- Prints or returns list of keys containing the string sub, default is all.
- Source
- ------
- The values of the constants provided at this site are recommended for
- international use by CODATA and are the latest available. Termed the "2018
- CODATA recommended values," they are generally recognized worldwide for use in
- all fields of science and technology. The values became available on 20 May
- 2019 and replaced the 2014 CODATA set. Also available is an introduction to the
- constants for non-experts at
- https://physics.nist.gov/cuu/Constants/introduction.html
- References
- ----------
- Theoretical and experimental publications relevant to the fundamental constants
- and closely related precision measurements published since the mid 1980s, but
- also including many older papers of particular interest, some of which date
- back to the 1800s. To search the bibliography, visit
- https://physics.nist.gov/cuu/Constants/
- """
- import warnings
- from math import pi, sqrt
- from typing import Any
- __all__ = ['physical_constants', 'value', 'unit', 'precision', 'find',
- 'ConstantWarning']
- """
- Source: https://physics.nist.gov/cuu/Constants/
- The values of the constants provided at this site are recommended for
- international use by CODATA and are the latest available. Termed the "2018
- CODATA recommended values," they are generally recognized worldwide for use in
- all fields of science and technology. The values became available on 20 May
- 2019 and replaced the 2014 CODATA set.
- """
- #
- # Source: https://physics.nist.gov/cuu/Constants/
- #
- # Quantity Value Uncertainty Unit
- # ---------------------------------------------------- --------------------- -------------------- -------------
- txt2002 = """\
- Wien displacement law constant 2.897 7685e-3 0.000 0051e-3 m K
- atomic unit of 1st hyperpolarizablity 3.206 361 51e-53 0.000 000 28e-53 C^3 m^3 J^-2
- atomic unit of 2nd hyperpolarizablity 6.235 3808e-65 0.000 0011e-65 C^4 m^4 J^-3
- atomic unit of electric dipole moment 8.478 353 09e-30 0.000 000 73e-30 C m
- atomic unit of electric polarizablity 1.648 777 274e-41 0.000 000 016e-41 C^2 m^2 J^-1
- atomic unit of electric quadrupole moment 4.486 551 24e-40 0.000 000 39e-40 C m^2
- atomic unit of magn. dipole moment 1.854 801 90e-23 0.000 000 16e-23 J T^-1
- atomic unit of magn. flux density 2.350 517 42e5 0.000 000 20e5 T
- deuteron magn. moment 0.433 073 482e-26 0.000 000 038e-26 J T^-1
- deuteron magn. moment to Bohr magneton ratio 0.466 975 4567e-3 0.000 000 0050e-3
- deuteron magn. moment to nuclear magneton ratio 0.857 438 2329 0.000 000 0092
- deuteron-electron magn. moment ratio -4.664 345 548e-4 0.000 000 050e-4
- deuteron-proton magn. moment ratio 0.307 012 2084 0.000 000 0045
- deuteron-neutron magn. moment ratio -0.448 206 52 0.000 000 11
- electron gyromagn. ratio 1.760 859 74e11 0.000 000 15e11 s^-1 T^-1
- electron gyromagn. ratio over 2 pi 28 024.9532 0.0024 MHz T^-1
- electron magn. moment -928.476 412e-26 0.000 080e-26 J T^-1
- electron magn. moment to Bohr magneton ratio -1.001 159 652 1859 0.000 000 000 0038
- electron magn. moment to nuclear magneton ratio -1838.281 971 07 0.000 000 85
- electron magn. moment anomaly 1.159 652 1859e-3 0.000 000 0038e-3
- electron to shielded proton magn. moment ratio -658.227 5956 0.000 0071
- electron to shielded helion magn. moment ratio 864.058 255 0.000 010
- electron-deuteron magn. moment ratio -2143.923 493 0.000 023
- electron-muon magn. moment ratio 206.766 9894 0.000 0054
- electron-neutron magn. moment ratio 960.920 50 0.000 23
- electron-proton magn. moment ratio -658.210 6862 0.000 0066
- magn. constant 12.566 370 614...e-7 0 N A^-2
- magn. flux quantum 2.067 833 72e-15 0.000 000 18e-15 Wb
- muon magn. moment -4.490 447 99e-26 0.000 000 40e-26 J T^-1
- muon magn. moment to Bohr magneton ratio -4.841 970 45e-3 0.000 000 13e-3
- muon magn. moment to nuclear magneton ratio -8.890 596 98 0.000 000 23
- muon-proton magn. moment ratio -3.183 345 118 0.000 000 089
- neutron gyromagn. ratio 1.832 471 83e8 0.000 000 46e8 s^-1 T^-1
- neutron gyromagn. ratio over 2 pi 29.164 6950 0.000 0073 MHz T^-1
- neutron magn. moment -0.966 236 45e-26 0.000 000 24e-26 J T^-1
- neutron magn. moment to Bohr magneton ratio -1.041 875 63e-3 0.000 000 25e-3
- neutron magn. moment to nuclear magneton ratio -1.913 042 73 0.000 000 45
- neutron to shielded proton magn. moment ratio -0.684 996 94 0.000 000 16
- neutron-electron magn. moment ratio 1.040 668 82e-3 0.000 000 25e-3
- neutron-proton magn. moment ratio -0.684 979 34 0.000 000 16
- proton gyromagn. ratio 2.675 222 05e8 0.000 000 23e8 s^-1 T^-1
- proton gyromagn. ratio over 2 pi 42.577 4813 0.000 0037 MHz T^-1
- proton magn. moment 1.410 606 71e-26 0.000 000 12e-26 J T^-1
- proton magn. moment to Bohr magneton ratio 1.521 032 206e-3 0.000 000 015e-3
- proton magn. moment to nuclear magneton ratio 2.792 847 351 0.000 000 028
- proton magn. shielding correction 25.689e-6 0.015e-6
- proton-neutron magn. moment ratio -1.459 898 05 0.000 000 34
- shielded helion gyromagn. ratio 2.037 894 70e8 0.000 000 18e8 s^-1 T^-1
- shielded helion gyromagn. ratio over 2 pi 32.434 1015 0.000 0028 MHz T^-1
- shielded helion magn. moment -1.074 553 024e-26 0.000 000 093e-26 J T^-1
- shielded helion magn. moment to Bohr magneton ratio -1.158 671 474e-3 0.000 000 014e-3
- shielded helion magn. moment to nuclear magneton ratio -2.127 497 723 0.000 000 025
- shielded helion to proton magn. moment ratio -0.761 766 562 0.000 000 012
- shielded helion to shielded proton magn. moment ratio -0.761 786 1313 0.000 000 0033
- shielded helion gyromagn. ratio 2.037 894 70e8 0.000 000 18e8 s^-1 T^-1
- shielded helion gyromagn. ratio over 2 pi 32.434 1015 0.000 0028 MHz T^-1
- shielded proton magn. moment 1.410 570 47e-26 0.000 000 12e-26 J T^-1
- shielded proton magn. moment to Bohr magneton ratio 1.520 993 132e-3 0.000 000 016e-3
- shielded proton magn. moment to nuclear magneton ratio 2.792 775 604 0.000 000 030
- {220} lattice spacing of silicon 192.015 5965e-12 0.000 0070e-12 m"""
- txt2006 = """\
- lattice spacing of silicon 192.015 5762 e-12 0.000 0050 e-12 m
- alpha particle-electron mass ratio 7294.299 5365 0.000 0031
- alpha particle mass 6.644 656 20 e-27 0.000 000 33 e-27 kg
- alpha particle mass energy equivalent 5.971 919 17 e-10 0.000 000 30 e-10 J
- alpha particle mass energy equivalent in MeV 3727.379 109 0.000 093 MeV
- alpha particle mass in u 4.001 506 179 127 0.000 000 000 062 u
- alpha particle molar mass 4.001 506 179 127 e-3 0.000 000 000 062 e-3 kg mol^-1
- alpha particle-proton mass ratio 3.972 599 689 51 0.000 000 000 41
- Angstrom star 1.000 014 98 e-10 0.000 000 90 e-10 m
- atomic mass constant 1.660 538 782 e-27 0.000 000 083 e-27 kg
- atomic mass constant energy equivalent 1.492 417 830 e-10 0.000 000 074 e-10 J
- atomic mass constant energy equivalent in MeV 931.494 028 0.000 023 MeV
- atomic mass unit-electron volt relationship 931.494 028 e6 0.000 023 e6 eV
- atomic mass unit-hartree relationship 3.423 177 7149 e7 0.000 000 0049 e7 E_h
- atomic mass unit-hertz relationship 2.252 342 7369 e23 0.000 000 0032 e23 Hz
- atomic mass unit-inverse meter relationship 7.513 006 671 e14 0.000 000 011 e14 m^-1
- atomic mass unit-joule relationship 1.492 417 830 e-10 0.000 000 074 e-10 J
- atomic mass unit-kelvin relationship 1.080 9527 e13 0.000 0019 e13 K
- atomic mass unit-kilogram relationship 1.660 538 782 e-27 0.000 000 083 e-27 kg
- atomic unit of 1st hyperpolarizability 3.206 361 533 e-53 0.000 000 081 e-53 C^3 m^3 J^-2
- atomic unit of 2nd hyperpolarizability 6.235 380 95 e-65 0.000 000 31 e-65 C^4 m^4 J^-3
- atomic unit of action 1.054 571 628 e-34 0.000 000 053 e-34 J s
- atomic unit of charge 1.602 176 487 e-19 0.000 000 040 e-19 C
- atomic unit of charge density 1.081 202 300 e12 0.000 000 027 e12 C m^-3
- atomic unit of current 6.623 617 63 e-3 0.000 000 17 e-3 A
- atomic unit of electric dipole mom. 8.478 352 81 e-30 0.000 000 21 e-30 C m
- atomic unit of electric field 5.142 206 32 e11 0.000 000 13 e11 V m^-1
- atomic unit of electric field gradient 9.717 361 66 e21 0.000 000 24 e21 V m^-2
- atomic unit of electric polarizability 1.648 777 2536 e-41 0.000 000 0034 e-41 C^2 m^2 J^-1
- atomic unit of electric potential 27.211 383 86 0.000 000 68 V
- atomic unit of electric quadrupole mom. 4.486 551 07 e-40 0.000 000 11 e-40 C m^2
- atomic unit of energy 4.359 743 94 e-18 0.000 000 22 e-18 J
- atomic unit of force 8.238 722 06 e-8 0.000 000 41 e-8 N
- atomic unit of length 0.529 177 208 59 e-10 0.000 000 000 36 e-10 m
- atomic unit of mag. dipole mom. 1.854 801 830 e-23 0.000 000 046 e-23 J T^-1
- atomic unit of mag. flux density 2.350 517 382 e5 0.000 000 059 e5 T
- atomic unit of magnetizability 7.891 036 433 e-29 0.000 000 027 e-29 J T^-2
- atomic unit of mass 9.109 382 15 e-31 0.000 000 45 e-31 kg
- atomic unit of momentum 1.992 851 565 e-24 0.000 000 099 e-24 kg m s^-1
- atomic unit of permittivity 1.112 650 056... e-10 (exact) F m^-1
- atomic unit of time 2.418 884 326 505 e-17 0.000 000 000 016 e-17 s
- atomic unit of velocity 2.187 691 2541 e6 0.000 000 0015 e6 m s^-1
- Avogadro constant 6.022 141 79 e23 0.000 000 30 e23 mol^-1
- Bohr magneton 927.400 915 e-26 0.000 023 e-26 J T^-1
- Bohr magneton in eV/T 5.788 381 7555 e-5 0.000 000 0079 e-5 eV T^-1
- Bohr magneton in Hz/T 13.996 246 04 e9 0.000 000 35 e9 Hz T^-1
- Bohr magneton in inverse meters per tesla 46.686 4515 0.000 0012 m^-1 T^-1
- Bohr magneton in K/T 0.671 7131 0.000 0012 K T^-1
- Bohr radius 0.529 177 208 59 e-10 0.000 000 000 36 e-10 m
- Boltzmann constant 1.380 6504 e-23 0.000 0024 e-23 J K^-1
- Boltzmann constant in eV/K 8.617 343 e-5 0.000 015 e-5 eV K^-1
- Boltzmann constant in Hz/K 2.083 6644 e10 0.000 0036 e10 Hz K^-1
- Boltzmann constant in inverse meters per kelvin 69.503 56 0.000 12 m^-1 K^-1
- characteristic impedance of vacuum 376.730 313 461... (exact) ohm
- classical electron radius 2.817 940 2894 e-15 0.000 000 0058 e-15 m
- Compton wavelength 2.426 310 2175 e-12 0.000 000 0033 e-12 m
- Compton wavelength over 2 pi 386.159 264 59 e-15 0.000 000 53 e-15 m
- conductance quantum 7.748 091 7004 e-5 0.000 000 0053 e-5 S
- conventional value of Josephson constant 483 597.9 e9 (exact) Hz V^-1
- conventional value of von Klitzing constant 25 812.807 (exact) ohm
- Cu x unit 1.002 076 99 e-13 0.000 000 28 e-13 m
- deuteron-electron mag. mom. ratio -4.664 345 537 e-4 0.000 000 039 e-4
- deuteron-electron mass ratio 3670.482 9654 0.000 0016
- deuteron g factor 0.857 438 2308 0.000 000 0072
- deuteron mag. mom. 0.433 073 465 e-26 0.000 000 011 e-26 J T^-1
- deuteron mag. mom. to Bohr magneton ratio 0.466 975 4556 e-3 0.000 000 0039 e-3
- deuteron mag. mom. to nuclear magneton ratio 0.857 438 2308 0.000 000 0072
- deuteron mass 3.343 583 20 e-27 0.000 000 17 e-27 kg
- deuteron mass energy equivalent 3.005 062 72 e-10 0.000 000 15 e-10 J
- deuteron mass energy equivalent in MeV 1875.612 793 0.000 047 MeV
- deuteron mass in u 2.013 553 212 724 0.000 000 000 078 u
- deuteron molar mass 2.013 553 212 724 e-3 0.000 000 000 078 e-3 kg mol^-1
- deuteron-neutron mag. mom. ratio -0.448 206 52 0.000 000 11
- deuteron-proton mag. mom. ratio 0.307 012 2070 0.000 000 0024
- deuteron-proton mass ratio 1.999 007 501 08 0.000 000 000 22
- deuteron rms charge radius 2.1402 e-15 0.0028 e-15 m
- electric constant 8.854 187 817... e-12 (exact) F m^-1
- electron charge to mass quotient -1.758 820 150 e11 0.000 000 044 e11 C kg^-1
- electron-deuteron mag. mom. ratio -2143.923 498 0.000 018
- electron-deuteron mass ratio 2.724 437 1093 e-4 0.000 000 0012 e-4
- electron g factor -2.002 319 304 3622 0.000 000 000 0015
- electron gyromag. ratio 1.760 859 770 e11 0.000 000 044 e11 s^-1 T^-1
- electron gyromag. ratio over 2 pi 28 024.953 64 0.000 70 MHz T^-1
- electron mag. mom. -928.476 377 e-26 0.000 023 e-26 J T^-1
- electron mag. mom. anomaly 1.159 652 181 11 e-3 0.000 000 000 74 e-3
- electron mag. mom. to Bohr magneton ratio -1.001 159 652 181 11 0.000 000 000 000 74
- electron mag. mom. to nuclear magneton ratio -1838.281 970 92 0.000 000 80
- electron mass 9.109 382 15 e-31 0.000 000 45 e-31 kg
- electron mass energy equivalent 8.187 104 38 e-14 0.000 000 41 e-14 J
- electron mass energy equivalent in MeV 0.510 998 910 0.000 000 013 MeV
- electron mass in u 5.485 799 0943 e-4 0.000 000 0023 e-4 u
- electron molar mass 5.485 799 0943 e-7 0.000 000 0023 e-7 kg mol^-1
- electron-muon mag. mom. ratio 206.766 9877 0.000 0052
- electron-muon mass ratio 4.836 331 71 e-3 0.000 000 12 e-3
- electron-neutron mag. mom. ratio 960.920 50 0.000 23
- electron-neutron mass ratio 5.438 673 4459 e-4 0.000 000 0033 e-4
- electron-proton mag. mom. ratio -658.210 6848 0.000 0054
- electron-proton mass ratio 5.446 170 2177 e-4 0.000 000 0024 e-4
- electron-tau mass ratio 2.875 64 e-4 0.000 47 e-4
- electron to alpha particle mass ratio 1.370 933 555 70 e-4 0.000 000 000 58 e-4
- electron to shielded helion mag. mom. ratio 864.058 257 0.000 010
- electron to shielded proton mag. mom. ratio -658.227 5971 0.000 0072
- electron volt 1.602 176 487 e-19 0.000 000 040 e-19 J
- electron volt-atomic mass unit relationship 1.073 544 188 e-9 0.000 000 027 e-9 u
- electron volt-hartree relationship 3.674 932 540 e-2 0.000 000 092 e-2 E_h
- electron volt-hertz relationship 2.417 989 454 e14 0.000 000 060 e14 Hz
- electron volt-inverse meter relationship 8.065 544 65 e5 0.000 000 20 e5 m^-1
- electron volt-joule relationship 1.602 176 487 e-19 0.000 000 040 e-19 J
- electron volt-kelvin relationship 1.160 4505 e4 0.000 0020 e4 K
- electron volt-kilogram relationship 1.782 661 758 e-36 0.000 000 044 e-36 kg
- elementary charge 1.602 176 487 e-19 0.000 000 040 e-19 C
- elementary charge over h 2.417 989 454 e14 0.000 000 060 e14 A J^-1
- Faraday constant 96 485.3399 0.0024 C mol^-1
- Faraday constant for conventional electric current 96 485.3401 0.0048 C_90 mol^-1
- Fermi coupling constant 1.166 37 e-5 0.000 01 e-5 GeV^-2
- fine-structure constant 7.297 352 5376 e-3 0.000 000 0050 e-3
- first radiation constant 3.741 771 18 e-16 0.000 000 19 e-16 W m^2
- first radiation constant for spectral radiance 1.191 042 759 e-16 0.000 000 059 e-16 W m^2 sr^-1
- hartree-atomic mass unit relationship 2.921 262 2986 e-8 0.000 000 0042 e-8 u
- hartree-electron volt relationship 27.211 383 86 0.000 000 68 eV
- Hartree energy 4.359 743 94 e-18 0.000 000 22 e-18 J
- Hartree energy in eV 27.211 383 86 0.000 000 68 eV
- hartree-hertz relationship 6.579 683 920 722 e15 0.000 000 000 044 e15 Hz
- hartree-inverse meter relationship 2.194 746 313 705 e7 0.000 000 000 015 e7 m^-1
- hartree-joule relationship 4.359 743 94 e-18 0.000 000 22 e-18 J
- hartree-kelvin relationship 3.157 7465 e5 0.000 0055 e5 K
- hartree-kilogram relationship 4.850 869 34 e-35 0.000 000 24 e-35 kg
- helion-electron mass ratio 5495.885 2765 0.000 0052
- helion mass 5.006 411 92 e-27 0.000 000 25 e-27 kg
- helion mass energy equivalent 4.499 538 64 e-10 0.000 000 22 e-10 J
- helion mass energy equivalent in MeV 2808.391 383 0.000 070 MeV
- helion mass in u 3.014 932 2473 0.000 000 0026 u
- helion molar mass 3.014 932 2473 e-3 0.000 000 0026 e-3 kg mol^-1
- helion-proton mass ratio 2.993 152 6713 0.000 000 0026
- hertz-atomic mass unit relationship 4.439 821 6294 e-24 0.000 000 0064 e-24 u
- hertz-electron volt relationship 4.135 667 33 e-15 0.000 000 10 e-15 eV
- hertz-hartree relationship 1.519 829 846 006 e-16 0.000 000 000010e-16 E_h
- hertz-inverse meter relationship 3.335 640 951... e-9 (exact) m^-1
- hertz-joule relationship 6.626 068 96 e-34 0.000 000 33 e-34 J
- hertz-kelvin relationship 4.799 2374 e-11 0.000 0084 e-11 K
- hertz-kilogram relationship 7.372 496 00 e-51 0.000 000 37 e-51 kg
- inverse fine-structure constant 137.035 999 679 0.000 000 094
- inverse meter-atomic mass unit relationship 1.331 025 0394 e-15 0.000 000 0019 e-15 u
- inverse meter-electron volt relationship 1.239 841 875 e-6 0.000 000 031 e-6 eV
- inverse meter-hartree relationship 4.556 335 252 760 e-8 0.000 000 000 030 e-8 E_h
- inverse meter-hertz relationship 299 792 458 (exact) Hz
- inverse meter-joule relationship 1.986 445 501 e-25 0.000 000 099 e-25 J
- inverse meter-kelvin relationship 1.438 7752 e-2 0.000 0025 e-2 K
- inverse meter-kilogram relationship 2.210 218 70 e-42 0.000 000 11 e-42 kg
- inverse of conductance quantum 12 906.403 7787 0.000 0088 ohm
- Josephson constant 483 597.891 e9 0.012 e9 Hz V^-1
- joule-atomic mass unit relationship 6.700 536 41 e9 0.000 000 33 e9 u
- joule-electron volt relationship 6.241 509 65 e18 0.000 000 16 e18 eV
- joule-hartree relationship 2.293 712 69 e17 0.000 000 11 e17 E_h
- joule-hertz relationship 1.509 190 450 e33 0.000 000 075 e33 Hz
- joule-inverse meter relationship 5.034 117 47 e24 0.000 000 25 e24 m^-1
- joule-kelvin relationship 7.242 963 e22 0.000 013 e22 K
- joule-kilogram relationship 1.112 650 056... e-17 (exact) kg
- kelvin-atomic mass unit relationship 9.251 098 e-14 0.000 016 e-14 u
- kelvin-electron volt relationship 8.617 343 e-5 0.000 015 e-5 eV
- kelvin-hartree relationship 3.166 8153 e-6 0.000 0055 e-6 E_h
- kelvin-hertz relationship 2.083 6644 e10 0.000 0036 e10 Hz
- kelvin-inverse meter relationship 69.503 56 0.000 12 m^-1
- kelvin-joule relationship 1.380 6504 e-23 0.000 0024 e-23 J
- kelvin-kilogram relationship 1.536 1807 e-40 0.000 0027 e-40 kg
- kilogram-atomic mass unit relationship 6.022 141 79 e26 0.000 000 30 e26 u
- kilogram-electron volt relationship 5.609 589 12 e35 0.000 000 14 e35 eV
- kilogram-hartree relationship 2.061 486 16 e34 0.000 000 10 e34 E_h
- kilogram-hertz relationship 1.356 392 733 e50 0.000 000 068 e50 Hz
- kilogram-inverse meter relationship 4.524 439 15 e41 0.000 000 23 e41 m^-1
- kilogram-joule relationship 8.987 551 787... e16 (exact) J
- kilogram-kelvin relationship 6.509 651 e39 0.000 011 e39 K
- lattice parameter of silicon 543.102 064 e-12 0.000 014 e-12 m
- Loschmidt constant (273.15 K, 101.325 kPa) 2.686 7774 e25 0.000 0047 e25 m^-3
- mag. constant 12.566 370 614... e-7 (exact) N A^-2
- mag. flux quantum 2.067 833 667 e-15 0.000 000 052 e-15 Wb
- molar gas constant 8.314 472 0.000 015 J mol^-1 K^-1
- molar mass constant 1 e-3 (exact) kg mol^-1
- molar mass of carbon-12 12 e-3 (exact) kg mol^-1
- molar Planck constant 3.990 312 6821 e-10 0.000 000 0057 e-10 J s mol^-1
- molar Planck constant times c 0.119 626 564 72 0.000 000 000 17 J m mol^-1
- molar volume of ideal gas (273.15 K, 100 kPa) 22.710 981 e-3 0.000 040 e-3 m^3 mol^-1
- molar volume of ideal gas (273.15 K, 101.325 kPa) 22.413 996 e-3 0.000 039 e-3 m^3 mol^-1
- molar volume of silicon 12.058 8349 e-6 0.000 0011 e-6 m^3 mol^-1
- Mo x unit 1.002 099 55 e-13 0.000 000 53 e-13 m
- muon Compton wavelength 11.734 441 04 e-15 0.000 000 30 e-15 m
- muon Compton wavelength over 2 pi 1.867 594 295 e-15 0.000 000 047 e-15 m
- muon-electron mass ratio 206.768 2823 0.000 0052
- muon g factor -2.002 331 8414 0.000 000 0012
- muon mag. mom. -4.490 447 86 e-26 0.000 000 16 e-26 J T^-1
- muon mag. mom. anomaly 1.165 920 69 e-3 0.000 000 60 e-3
- muon mag. mom. to Bohr magneton ratio -4.841 970 49 e-3 0.000 000 12 e-3
- muon mag. mom. to nuclear magneton ratio -8.890 597 05 0.000 000 23
- muon mass 1.883 531 30 e-28 0.000 000 11 e-28 kg
- muon mass energy equivalent 1.692 833 510 e-11 0.000 000 095 e-11 J
- muon mass energy equivalent in MeV 105.658 3668 0.000 0038 MeV
- muon mass in u 0.113 428 9256 0.000 000 0029 u
- muon molar mass 0.113 428 9256 e-3 0.000 000 0029 e-3 kg mol^-1
- muon-neutron mass ratio 0.112 454 5167 0.000 000 0029
- muon-proton mag. mom. ratio -3.183 345 137 0.000 000 085
- muon-proton mass ratio 0.112 609 5261 0.000 000 0029
- muon-tau mass ratio 5.945 92 e-2 0.000 97 e-2
- natural unit of action 1.054 571 628 e-34 0.000 000 053 e-34 J s
- natural unit of action in eV s 6.582 118 99 e-16 0.000 000 16 e-16 eV s
- natural unit of energy 8.187 104 38 e-14 0.000 000 41 e-14 J
- natural unit of energy in MeV 0.510 998 910 0.000 000 013 MeV
- natural unit of length 386.159 264 59 e-15 0.000 000 53 e-15 m
- natural unit of mass 9.109 382 15 e-31 0.000 000 45 e-31 kg
- natural unit of momentum 2.730 924 06 e-22 0.000 000 14 e-22 kg m s^-1
- natural unit of momentum in MeV/c 0.510 998 910 0.000 000 013 MeV/c
- natural unit of time 1.288 088 6570 e-21 0.000 000 0018 e-21 s
- natural unit of velocity 299 792 458 (exact) m s^-1
- neutron Compton wavelength 1.319 590 8951 e-15 0.000 000 0020 e-15 m
- neutron Compton wavelength over 2 pi 0.210 019 413 82 e-15 0.000 000 000 31 e-15 m
- neutron-electron mag. mom. ratio 1.040 668 82 e-3 0.000 000 25 e-3
- neutron-electron mass ratio 1838.683 6605 0.000 0011
- neutron g factor -3.826 085 45 0.000 000 90
- neutron gyromag. ratio 1.832 471 85 e8 0.000 000 43 e8 s^-1 T^-1
- neutron gyromag. ratio over 2 pi 29.164 6954 0.000 0069 MHz T^-1
- neutron mag. mom. -0.966 236 41 e-26 0.000 000 23 e-26 J T^-1
- neutron mag. mom. to Bohr magneton ratio -1.041 875 63 e-3 0.000 000 25 e-3
- neutron mag. mom. to nuclear magneton ratio -1.913 042 73 0.000 000 45
- neutron mass 1.674 927 211 e-27 0.000 000 084 e-27 kg
- neutron mass energy equivalent 1.505 349 505 e-10 0.000 000 075 e-10 J
- neutron mass energy equivalent in MeV 939.565 346 0.000 023 MeV
- neutron mass in u 1.008 664 915 97 0.000 000 000 43 u
- neutron molar mass 1.008 664 915 97 e-3 0.000 000 000 43 e-3 kg mol^-1
- neutron-muon mass ratio 8.892 484 09 0.000 000 23
- neutron-proton mag. mom. ratio -0.684 979 34 0.000 000 16
- neutron-proton mass ratio 1.001 378 419 18 0.000 000 000 46
- neutron-tau mass ratio 0.528 740 0.000 086
- neutron to shielded proton mag. mom. ratio -0.684 996 94 0.000 000 16
- Newtonian constant of gravitation 6.674 28 e-11 0.000 67 e-11 m^3 kg^-1 s^-2
- Newtonian constant of gravitation over h-bar c 6.708 81 e-39 0.000 67 e-39 (GeV/c^2)^-2
- nuclear magneton 5.050 783 24 e-27 0.000 000 13 e-27 J T^-1
- nuclear magneton in eV/T 3.152 451 2326 e-8 0.000 000 0045 e-8 eV T^-1
- nuclear magneton in inverse meters per tesla 2.542 623 616 e-2 0.000 000 064 e-2 m^-1 T^-1
- nuclear magneton in K/T 3.658 2637 e-4 0.000 0064 e-4 K T^-1
- nuclear magneton in MHz/T 7.622 593 84 0.000 000 19 MHz T^-1
- Planck constant 6.626 068 96 e-34 0.000 000 33 e-34 J s
- Planck constant in eV s 4.135 667 33 e-15 0.000 000 10 e-15 eV s
- Planck constant over 2 pi 1.054 571 628 e-34 0.000 000 053 e-34 J s
- Planck constant over 2 pi in eV s 6.582 118 99 e-16 0.000 000 16 e-16 eV s
- Planck constant over 2 pi times c in MeV fm 197.326 9631 0.000 0049 MeV fm
- Planck length 1.616 252 e-35 0.000 081 e-35 m
- Planck mass 2.176 44 e-8 0.000 11 e-8 kg
- Planck mass energy equivalent in GeV 1.220 892 e19 0.000 061 e19 GeV
- Planck temperature 1.416 785 e32 0.000 071 e32 K
- Planck time 5.391 24 e-44 0.000 27 e-44 s
- proton charge to mass quotient 9.578 833 92 e7 0.000 000 24 e7 C kg^-1
- proton Compton wavelength 1.321 409 8446 e-15 0.000 000 0019 e-15 m
- proton Compton wavelength over 2 pi 0.210 308 908 61 e-15 0.000 000 000 30 e-15 m
- proton-electron mass ratio 1836.152 672 47 0.000 000 80
- proton g factor 5.585 694 713 0.000 000 046
- proton gyromag. ratio 2.675 222 099 e8 0.000 000 070 e8 s^-1 T^-1
- proton gyromag. ratio over 2 pi 42.577 4821 0.000 0011 MHz T^-1
- proton mag. mom. 1.410 606 662 e-26 0.000 000 037 e-26 J T^-1
- proton mag. mom. to Bohr magneton ratio 1.521 032 209 e-3 0.000 000 012 e-3
- proton mag. mom. to nuclear magneton ratio 2.792 847 356 0.000 000 023
- proton mag. shielding correction 25.694 e-6 0.014 e-6
- proton mass 1.672 621 637 e-27 0.000 000 083 e-27 kg
- proton mass energy equivalent 1.503 277 359 e-10 0.000 000 075 e-10 J
- proton mass energy equivalent in MeV 938.272 013 0.000 023 MeV
- proton mass in u 1.007 276 466 77 0.000 000 000 10 u
- proton molar mass 1.007 276 466 77 e-3 0.000 000 000 10 e-3 kg mol^-1
- proton-muon mass ratio 8.880 243 39 0.000 000 23
- proton-neutron mag. mom. ratio -1.459 898 06 0.000 000 34
- proton-neutron mass ratio 0.998 623 478 24 0.000 000 000 46
- proton rms charge radius 0.8768 e-15 0.0069 e-15 m
- proton-tau mass ratio 0.528 012 0.000 086
- quantum of circulation 3.636 947 5199 e-4 0.000 000 0050 e-4 m^2 s^-1
- quantum of circulation times 2 7.273 895 040 e-4 0.000 000 010 e-4 m^2 s^-1
- Rydberg constant 10 973 731.568 527 0.000 073 m^-1
- Rydberg constant times c in Hz 3.289 841 960 361 e15 0.000 000 000 022 e15 Hz
- Rydberg constant times hc in eV 13.605 691 93 0.000 000 34 eV
- Rydberg constant times hc in J 2.179 871 97 e-18 0.000 000 11 e-18 J
- Sackur-Tetrode constant (1 K, 100 kPa) -1.151 7047 0.000 0044
- Sackur-Tetrode constant (1 K, 101.325 kPa) -1.164 8677 0.000 0044
- second radiation constant 1.438 7752 e-2 0.000 0025 e-2 m K
- shielded helion gyromag. ratio 2.037 894 730 e8 0.000 000 056 e8 s^-1 T^-1
- shielded helion gyromag. ratio over 2 pi 32.434 101 98 0.000 000 90 MHz T^-1
- shielded helion mag. mom. -1.074 552 982 e-26 0.000 000 030 e-26 J T^-1
- shielded helion mag. mom. to Bohr magneton ratio -1.158 671 471 e-3 0.000 000 014 e-3
- shielded helion mag. mom. to nuclear magneton ratio -2.127 497 718 0.000 000 025
- shielded helion to proton mag. mom. ratio -0.761 766 558 0.000 000 011
- shielded helion to shielded proton mag. mom. ratio -0.761 786 1313 0.000 000 0033
- shielded proton gyromag. ratio 2.675 153 362 e8 0.000 000 073 e8 s^-1 T^-1
- shielded proton gyromag. ratio over 2 pi 42.576 3881 0.000 0012 MHz T^-1
- shielded proton mag. mom. 1.410 570 419 e-26 0.000 000 038 e-26 J T^-1
- shielded proton mag. mom. to Bohr magneton ratio 1.520 993 128 e-3 0.000 000 017 e-3
- shielded proton mag. mom. to nuclear magneton ratio 2.792 775 598 0.000 000 030
- speed of light in vacuum 299 792 458 (exact) m s^-1
- standard acceleration of gravity 9.806 65 (exact) m s^-2
- standard atmosphere 101 325 (exact) Pa
- Stefan-Boltzmann constant 5.670 400 e-8 0.000 040 e-8 W m^-2 K^-4
- tau Compton wavelength 0.697 72 e-15 0.000 11 e-15 m
- tau Compton wavelength over 2 pi 0.111 046 e-15 0.000 018 e-15 m
- tau-electron mass ratio 3477.48 0.57
- tau mass 3.167 77 e-27 0.000 52 e-27 kg
- tau mass energy equivalent 2.847 05 e-10 0.000 46 e-10 J
- tau mass energy equivalent in MeV 1776.99 0.29 MeV
- tau mass in u 1.907 68 0.000 31 u
- tau molar mass 1.907 68 e-3 0.000 31 e-3 kg mol^-1
- tau-muon mass ratio 16.8183 0.0027
- tau-neutron mass ratio 1.891 29 0.000 31
- tau-proton mass ratio 1.893 90 0.000 31
- Thomson cross section 0.665 245 8558 e-28 0.000 000 0027 e-28 m^2
- triton-electron mag. mom. ratio -1.620 514 423 e-3 0.000 000 021 e-3
- triton-electron mass ratio 5496.921 5269 0.000 0051
- triton g factor 5.957 924 896 0.000 000 076
- triton mag. mom. 1.504 609 361 e-26 0.000 000 042 e-26 J T^-1
- triton mag. mom. to Bohr magneton ratio 1.622 393 657 e-3 0.000 000 021 e-3
- triton mag. mom. to nuclear magneton ratio 2.978 962 448 0.000 000 038
- triton mass 5.007 355 88 e-27 0.000 000 25 e-27 kg
- triton mass energy equivalent 4.500 387 03 e-10 0.000 000 22 e-10 J
- triton mass energy equivalent in MeV 2808.920 906 0.000 070 MeV
- triton mass in u 3.015 500 7134 0.000 000 0025 u
- triton molar mass 3.015 500 7134 e-3 0.000 000 0025 e-3 kg mol^-1
- triton-neutron mag. mom. ratio -1.557 185 53 0.000 000 37
- triton-proton mag. mom. ratio 1.066 639 908 0.000 000 010
- triton-proton mass ratio 2.993 717 0309 0.000 000 0025
- unified atomic mass unit 1.660 538 782 e-27 0.000 000 083 e-27 kg
- von Klitzing constant 25 812.807 557 0.000 018 ohm
- weak mixing angle 0.222 55 0.000 56
- Wien frequency displacement law constant 5.878 933 e10 0.000 010 e10 Hz K^-1
- Wien wavelength displacement law constant 2.897 7685 e-3 0.000 0051 e-3 m K"""
- txt2010 = """\
- {220} lattice spacing of silicon 192.015 5714 e-12 0.000 0032 e-12 m
- alpha particle-electron mass ratio 7294.299 5361 0.000 0029
- alpha particle mass 6.644 656 75 e-27 0.000 000 29 e-27 kg
- alpha particle mass energy equivalent 5.971 919 67 e-10 0.000 000 26 e-10 J
- alpha particle mass energy equivalent in MeV 3727.379 240 0.000 082 MeV
- alpha particle mass in u 4.001 506 179 125 0.000 000 000 062 u
- alpha particle molar mass 4.001 506 179 125 e-3 0.000 000 000 062 e-3 kg mol^-1
- alpha particle-proton mass ratio 3.972 599 689 33 0.000 000 000 36
- Angstrom star 1.000 014 95 e-10 0.000 000 90 e-10 m
- atomic mass constant 1.660 538 921 e-27 0.000 000 073 e-27 kg
- atomic mass constant energy equivalent 1.492 417 954 e-10 0.000 000 066 e-10 J
- atomic mass constant energy equivalent in MeV 931.494 061 0.000 021 MeV
- atomic mass unit-electron volt relationship 931.494 061 e6 0.000 021 e6 eV
- atomic mass unit-hartree relationship 3.423 177 6845 e7 0.000 000 0024 e7 E_h
- atomic mass unit-hertz relationship 2.252 342 7168 e23 0.000 000 0016 e23 Hz
- atomic mass unit-inverse meter relationship 7.513 006 6042 e14 0.000 000 0053 e14 m^-1
- atomic mass unit-joule relationship 1.492 417 954 e-10 0.000 000 066 e-10 J
- atomic mass unit-kelvin relationship 1.080 954 08 e13 0.000 000 98 e13 K
- atomic mass unit-kilogram relationship 1.660 538 921 e-27 0.000 000 073 e-27 kg
- atomic unit of 1st hyperpolarizability 3.206 361 449 e-53 0.000 000 071 e-53 C^3 m^3 J^-2
- atomic unit of 2nd hyperpolarizability 6.235 380 54 e-65 0.000 000 28 e-65 C^4 m^4 J^-3
- atomic unit of action 1.054 571 726 e-34 0.000 000 047 e-34 J s
- atomic unit of charge 1.602 176 565 e-19 0.000 000 035 e-19 C
- atomic unit of charge density 1.081 202 338 e12 0.000 000 024 e12 C m^-3
- atomic unit of current 6.623 617 95 e-3 0.000 000 15 e-3 A
- atomic unit of electric dipole mom. 8.478 353 26 e-30 0.000 000 19 e-30 C m
- atomic unit of electric field 5.142 206 52 e11 0.000 000 11 e11 V m^-1
- atomic unit of electric field gradient 9.717 362 00 e21 0.000 000 21 e21 V m^-2
- atomic unit of electric polarizability 1.648 777 2754 e-41 0.000 000 0016 e-41 C^2 m^2 J^-1
- atomic unit of electric potential 27.211 385 05 0.000 000 60 V
- atomic unit of electric quadrupole mom. 4.486 551 331 e-40 0.000 000 099 e-40 C m^2
- atomic unit of energy 4.359 744 34 e-18 0.000 000 19 e-18 J
- atomic unit of force 8.238 722 78 e-8 0.000 000 36 e-8 N
- atomic unit of length 0.529 177 210 92 e-10 0.000 000 000 17 e-10 m
- atomic unit of mag. dipole mom. 1.854 801 936 e-23 0.000 000 041 e-23 J T^-1
- atomic unit of mag. flux density 2.350 517 464 e5 0.000 000 052 e5 T
- atomic unit of magnetizability 7.891 036 607 e-29 0.000 000 013 e-29 J T^-2
- atomic unit of mass 9.109 382 91 e-31 0.000 000 40 e-31 kg
- atomic unit of mom.um 1.992 851 740 e-24 0.000 000 088 e-24 kg m s^-1
- atomic unit of permittivity 1.112 650 056... e-10 (exact) F m^-1
- atomic unit of time 2.418 884 326 502e-17 0.000 000 000 012e-17 s
- atomic unit of velocity 2.187 691 263 79 e6 0.000 000 000 71 e6 m s^-1
- Avogadro constant 6.022 141 29 e23 0.000 000 27 e23 mol^-1
- Bohr magneton 927.400 968 e-26 0.000 020 e-26 J T^-1
- Bohr magneton in eV/T 5.788 381 8066 e-5 0.000 000 0038 e-5 eV T^-1
- Bohr magneton in Hz/T 13.996 245 55 e9 0.000 000 31 e9 Hz T^-1
- Bohr magneton in inverse meters per tesla 46.686 4498 0.000 0010 m^-1 T^-1
- Bohr magneton in K/T 0.671 713 88 0.000 000 61 K T^-1
- Bohr radius 0.529 177 210 92 e-10 0.000 000 000 17 e-10 m
- Boltzmann constant 1.380 6488 e-23 0.000 0013 e-23 J K^-1
- Boltzmann constant in eV/K 8.617 3324 e-5 0.000 0078 e-5 eV K^-1
- Boltzmann constant in Hz/K 2.083 6618 e10 0.000 0019 e10 Hz K^-1
- Boltzmann constant in inverse meters per kelvin 69.503 476 0.000 063 m^-1 K^-1
- characteristic impedance of vacuum 376.730 313 461... (exact) ohm
- classical electron radius 2.817 940 3267 e-15 0.000 000 0027 e-15 m
- Compton wavelength 2.426 310 2389 e-12 0.000 000 0016 e-12 m
- Compton wavelength over 2 pi 386.159 268 00 e-15 0.000 000 25 e-15 m
- conductance quantum 7.748 091 7346 e-5 0.000 000 0025 e-5 S
- conventional value of Josephson constant 483 597.9 e9 (exact) Hz V^-1
- conventional value of von Klitzing constant 25 812.807 (exact) ohm
- Cu x unit 1.002 076 97 e-13 0.000 000 28 e-13 m
- deuteron-electron mag. mom. ratio -4.664 345 537 e-4 0.000 000 039 e-4
- deuteron-electron mass ratio 3670.482 9652 0.000 0015
- deuteron g factor 0.857 438 2308 0.000 000 0072
- deuteron mag. mom. 0.433 073 489 e-26 0.000 000 010 e-26 J T^-1
- deuteron mag. mom. to Bohr magneton ratio 0.466 975 4556 e-3 0.000 000 0039 e-3
- deuteron mag. mom. to nuclear magneton ratio 0.857 438 2308 0.000 000 0072
- deuteron mass 3.343 583 48 e-27 0.000 000 15 e-27 kg
- deuteron mass energy equivalent 3.005 062 97 e-10 0.000 000 13 e-10 J
- deuteron mass energy equivalent in MeV 1875.612 859 0.000 041 MeV
- deuteron mass in u 2.013 553 212 712 0.000 000 000 077 u
- deuteron molar mass 2.013 553 212 712 e-3 0.000 000 000 077 e-3 kg mol^-1
- deuteron-neutron mag. mom. ratio -0.448 206 52 0.000 000 11
- deuteron-proton mag. mom. ratio 0.307 012 2070 0.000 000 0024
- deuteron-proton mass ratio 1.999 007 500 97 0.000 000 000 18
- deuteron rms charge radius 2.1424 e-15 0.0021 e-15 m
- electric constant 8.854 187 817... e-12 (exact) F m^-1
- electron charge to mass quotient -1.758 820 088 e11 0.000 000 039 e11 C kg^-1
- electron-deuteron mag. mom. ratio -2143.923 498 0.000 018
- electron-deuteron mass ratio 2.724 437 1095 e-4 0.000 000 0011 e-4
- electron g factor -2.002 319 304 361 53 0.000 000 000 000 53
- electron gyromag. ratio 1.760 859 708 e11 0.000 000 039 e11 s^-1 T^-1
- electron gyromag. ratio over 2 pi 28 024.952 66 0.000 62 MHz T^-1
- electron-helion mass ratio 1.819 543 0761 e-4 0.000 000 0017 e-4
- electron mag. mom. -928.476 430 e-26 0.000 021 e-26 J T^-1
- electron mag. mom. anomaly 1.159 652 180 76 e-3 0.000 000 000 27 e-3
- electron mag. mom. to Bohr magneton ratio -1.001 159 652 180 76 0.000 000 000 000 27
- electron mag. mom. to nuclear magneton ratio -1838.281 970 90 0.000 000 75
- electron mass 9.109 382 91 e-31 0.000 000 40 e-31 kg
- electron mass energy equivalent 8.187 105 06 e-14 0.000 000 36 e-14 J
- electron mass energy equivalent in MeV 0.510 998 928 0.000 000 011 MeV
- electron mass in u 5.485 799 0946 e-4 0.000 000 0022 e-4 u
- electron molar mass 5.485 799 0946 e-7 0.000 000 0022 e-7 kg mol^-1
- electron-muon mag. mom. ratio 206.766 9896 0.000 0052
- electron-muon mass ratio 4.836 331 66 e-3 0.000 000 12 e-3
- electron-neutron mag. mom. ratio 960.920 50 0.000 23
- electron-neutron mass ratio 5.438 673 4461 e-4 0.000 000 0032 e-4
- electron-proton mag. mom. ratio -658.210 6848 0.000 0054
- electron-proton mass ratio 5.446 170 2178 e-4 0.000 000 0022 e-4
- electron-tau mass ratio 2.875 92 e-4 0.000 26 e-4
- electron to alpha particle mass ratio 1.370 933 555 78 e-4 0.000 000 000 55 e-4
- electron to shielded helion mag. mom. ratio 864.058 257 0.000 010
- electron to shielded proton mag. mom. ratio -658.227 5971 0.000 0072
- electron-triton mass ratio 1.819 200 0653 e-4 0.000 000 0017 e-4
- electron volt 1.602 176 565 e-19 0.000 000 035 e-19 J
- electron volt-atomic mass unit relationship 1.073 544 150 e-9 0.000 000 024 e-9 u
- electron volt-hartree relationship 3.674 932 379 e-2 0.000 000 081 e-2 E_h
- electron volt-hertz relationship 2.417 989 348 e14 0.000 000 053 e14 Hz
- electron volt-inverse meter relationship 8.065 544 29 e5 0.000 000 18 e5 m^-1
- electron volt-joule relationship 1.602 176 565 e-19 0.000 000 035 e-19 J
- electron volt-kelvin relationship 1.160 4519 e4 0.000 0011 e4 K
- electron volt-kilogram relationship 1.782 661 845 e-36 0.000 000 039 e-36 kg
- elementary charge 1.602 176 565 e-19 0.000 000 035 e-19 C
- elementary charge over h 2.417 989 348 e14 0.000 000 053 e14 A J^-1
- Faraday constant 96 485.3365 0.0021 C mol^-1
- Faraday constant for conventional electric current 96 485.3321 0.0043 C_90 mol^-1
- Fermi coupling constant 1.166 364 e-5 0.000 005 e-5 GeV^-2
- fine-structure constant 7.297 352 5698 e-3 0.000 000 0024 e-3
- first radiation constant 3.741 771 53 e-16 0.000 000 17 e-16 W m^2
- first radiation constant for spectral radiance 1.191 042 869 e-16 0.000 000 053 e-16 W m^2 sr^-1
- hartree-atomic mass unit relationship 2.921 262 3246 e-8 0.000 000 0021 e-8 u
- hartree-electron volt relationship 27.211 385 05 0.000 000 60 eV
- Hartree energy 4.359 744 34 e-18 0.000 000 19 e-18 J
- Hartree energy in eV 27.211 385 05 0.000 000 60 eV
- hartree-hertz relationship 6.579 683 920 729 e15 0.000 000 000 033 e15 Hz
- hartree-inverse meter relationship 2.194 746 313 708 e7 0.000 000 000 011 e7 m^-1
- hartree-joule relationship 4.359 744 34 e-18 0.000 000 19 e-18 J
- hartree-kelvin relationship 3.157 7504 e5 0.000 0029 e5 K
- hartree-kilogram relationship 4.850 869 79 e-35 0.000 000 21 e-35 kg
- helion-electron mass ratio 5495.885 2754 0.000 0050
- helion g factor -4.255 250 613 0.000 000 050
- helion mag. mom. -1.074 617 486 e-26 0.000 000 027 e-26 J T^-1
- helion mag. mom. to Bohr magneton ratio -1.158 740 958 e-3 0.000 000 014 e-3
- helion mag. mom. to nuclear magneton ratio -2.127 625 306 0.000 000 025
- helion mass 5.006 412 34 e-27 0.000 000 22 e-27 kg
- helion mass energy equivalent 4.499 539 02 e-10 0.000 000 20 e-10 J
- helion mass energy equivalent in MeV 2808.391 482 0.000 062 MeV
- helion mass in u 3.014 932 2468 0.000 000 0025 u
- helion molar mass 3.014 932 2468 e-3 0.000 000 0025 e-3 kg mol^-1
- helion-proton mass ratio 2.993 152 6707 0.000 000 0025
- hertz-atomic mass unit relationship 4.439 821 6689 e-24 0.000 000 0031 e-24 u
- hertz-electron volt relationship 4.135 667 516 e-15 0.000 000 091 e-15 eV
- hertz-hartree relationship 1.519 829 8460045e-16 0.000 000 0000076e-16 E_h
- hertz-inverse meter relationship 3.335 640 951... e-9 (exact) m^-1
- hertz-joule relationship 6.626 069 57 e-34 0.000 000 29 e-34 J
- hertz-kelvin relationship 4.799 2434 e-11 0.000 0044 e-11 K
- hertz-kilogram relationship 7.372 496 68 e-51 0.000 000 33 e-51 kg
- inverse fine-structure constant 137.035 999 074 0.000 000 044
- inverse meter-atomic mass unit relationship 1.331 025 051 20 e-15 0.000 000 000 94 e-15 u
- inverse meter-electron volt relationship 1.239 841 930 e-6 0.000 000 027 e-6 eV
- inverse meter-hartree relationship 4.556 335 252 755 e-8 0.000 000 000 023 e-8 E_h
- inverse meter-hertz relationship 299 792 458 (exact) Hz
- inverse meter-joule relationship 1.986 445 684 e-25 0.000 000 088 e-25 J
- inverse meter-kelvin relationship 1.438 7770 e-2 0.000 0013 e-2 K
- inverse meter-kilogram relationship 2.210 218 902 e-42 0.000 000 098 e-42 kg
- inverse of conductance quantum 12 906.403 7217 0.000 0042 ohm
- Josephson constant 483 597.870 e9 0.011 e9 Hz V^-1
- joule-atomic mass unit relationship 6.700 535 85 e9 0.000 000 30 e9 u
- joule-electron volt relationship 6.241 509 34 e18 0.000 000 14 e18 eV
- joule-hartree relationship 2.293 712 48 e17 0.000 000 10 e17 E_h
- joule-hertz relationship 1.509 190 311 e33 0.000 000 067 e33 Hz
- joule-inverse meter relationship 5.034 117 01 e24 0.000 000 22 e24 m^-1
- joule-kelvin relationship 7.242 9716 e22 0.000 0066 e22 K
- joule-kilogram relationship 1.112 650 056... e-17 (exact) kg
- kelvin-atomic mass unit relationship 9.251 0868 e-14 0.000 0084 e-14 u
- kelvin-electron volt relationship 8.617 3324 e-5 0.000 0078 e-5 eV
- kelvin-hartree relationship 3.166 8114 e-6 0.000 0029 e-6 E_h
- kelvin-hertz relationship 2.083 6618 e10 0.000 0019 e10 Hz
- kelvin-inverse meter relationship 69.503 476 0.000 063 m^-1
- kelvin-joule relationship 1.380 6488 e-23 0.000 0013 e-23 J
- kelvin-kilogram relationship 1.536 1790 e-40 0.000 0014 e-40 kg
- kilogram-atomic mass unit relationship 6.022 141 29 e26 0.000 000 27 e26 u
- kilogram-electron volt relationship 5.609 588 85 e35 0.000 000 12 e35 eV
- kilogram-hartree relationship 2.061 485 968 e34 0.000 000 091 e34 E_h
- kilogram-hertz relationship 1.356 392 608 e50 0.000 000 060 e50 Hz
- kilogram-inverse meter relationship 4.524 438 73 e41 0.000 000 20 e41 m^-1
- kilogram-joule relationship 8.987 551 787... e16 (exact) J
- kilogram-kelvin relationship 6.509 6582 e39 0.000 0059 e39 K
- lattice parameter of silicon 543.102 0504 e-12 0.000 0089 e-12 m
- Loschmidt constant (273.15 K, 100 kPa) 2.651 6462 e25 0.000 0024 e25 m^-3
- Loschmidt constant (273.15 K, 101.325 kPa) 2.686 7805 e25 0.000 0024 e25 m^-3
- mag. constant 12.566 370 614... e-7 (exact) N A^-2
- mag. flux quantum 2.067 833 758 e-15 0.000 000 046 e-15 Wb
- molar gas constant 8.314 4621 0.000 0075 J mol^-1 K^-1
- molar mass constant 1 e-3 (exact) kg mol^-1
- molar mass of carbon-12 12 e-3 (exact) kg mol^-1
- molar Planck constant 3.990 312 7176 e-10 0.000 000 0028 e-10 J s mol^-1
- molar Planck constant times c 0.119 626 565 779 0.000 000 000 084 J m mol^-1
- molar volume of ideal gas (273.15 K, 100 kPa) 22.710 953 e-3 0.000 021 e-3 m^3 mol^-1
- molar volume of ideal gas (273.15 K, 101.325 kPa) 22.413 968 e-3 0.000 020 e-3 m^3 mol^-1
- molar volume of silicon 12.058 833 01 e-6 0.000 000 80 e-6 m^3 mol^-1
- Mo x unit 1.002 099 52 e-13 0.000 000 53 e-13 m
- muon Compton wavelength 11.734 441 03 e-15 0.000 000 30 e-15 m
- muon Compton wavelength over 2 pi 1.867 594 294 e-15 0.000 000 047 e-15 m
- muon-electron mass ratio 206.768 2843 0.000 0052
- muon g factor -2.002 331 8418 0.000 000 0013
- muon mag. mom. -4.490 448 07 e-26 0.000 000 15 e-26 J T^-1
- muon mag. mom. anomaly 1.165 920 91 e-3 0.000 000 63 e-3
- muon mag. mom. to Bohr magneton ratio -4.841 970 44 e-3 0.000 000 12 e-3
- muon mag. mom. to nuclear magneton ratio -8.890 596 97 0.000 000 22
- muon mass 1.883 531 475 e-28 0.000 000 096 e-28 kg
- muon mass energy equivalent 1.692 833 667 e-11 0.000 000 086 e-11 J
- muon mass energy equivalent in MeV 105.658 3715 0.000 0035 MeV
- muon mass in u 0.113 428 9267 0.000 000 0029 u
- muon molar mass 0.113 428 9267 e-3 0.000 000 0029 e-3 kg mol^-1
- muon-neutron mass ratio 0.112 454 5177 0.000 000 0028
- muon-proton mag. mom. ratio -3.183 345 107 0.000 000 084
- muon-proton mass ratio 0.112 609 5272 0.000 000 0028
- muon-tau mass ratio 5.946 49 e-2 0.000 54 e-2
- natural unit of action 1.054 571 726 e-34 0.000 000 047 e-34 J s
- natural unit of action in eV s 6.582 119 28 e-16 0.000 000 15 e-16 eV s
- natural unit of energy 8.187 105 06 e-14 0.000 000 36 e-14 J
- natural unit of energy in MeV 0.510 998 928 0.000 000 011 MeV
- natural unit of length 386.159 268 00 e-15 0.000 000 25 e-15 m
- natural unit of mass 9.109 382 91 e-31 0.000 000 40 e-31 kg
- natural unit of mom.um 2.730 924 29 e-22 0.000 000 12 e-22 kg m s^-1
- natural unit of mom.um in MeV/c 0.510 998 928 0.000 000 011 MeV/c
- natural unit of time 1.288 088 668 33 e-21 0.000 000 000 83 e-21 s
- natural unit of velocity 299 792 458 (exact) m s^-1
- neutron Compton wavelength 1.319 590 9068 e-15 0.000 000 0011 e-15 m
- neutron Compton wavelength over 2 pi 0.210 019 415 68 e-15 0.000 000 000 17 e-15 m
- neutron-electron mag. mom. ratio 1.040 668 82 e-3 0.000 000 25 e-3
- neutron-electron mass ratio 1838.683 6605 0.000 0011
- neutron g factor -3.826 085 45 0.000 000 90
- neutron gyromag. ratio 1.832 471 79 e8 0.000 000 43 e8 s^-1 T^-1
- neutron gyromag. ratio over 2 pi 29.164 6943 0.000 0069 MHz T^-1
- neutron mag. mom. -0.966 236 47 e-26 0.000 000 23 e-26 J T^-1
- neutron mag. mom. to Bohr magneton ratio -1.041 875 63 e-3 0.000 000 25 e-3
- neutron mag. mom. to nuclear magneton ratio -1.913 042 72 0.000 000 45
- neutron mass 1.674 927 351 e-27 0.000 000 074 e-27 kg
- neutron mass energy equivalent 1.505 349 631 e-10 0.000 000 066 e-10 J
- neutron mass energy equivalent in MeV 939.565 379 0.000 021 MeV
- neutron mass in u 1.008 664 916 00 0.000 000 000 43 u
- neutron molar mass 1.008 664 916 00 e-3 0.000 000 000 43 e-3 kg mol^-1
- neutron-muon mass ratio 8.892 484 00 0.000 000 22
- neutron-proton mag. mom. ratio -0.684 979 34 0.000 000 16
- neutron-proton mass difference 2.305 573 92 e-30 0.000 000 76 e-30
- neutron-proton mass difference energy equivalent 2.072 146 50 e-13 0.000 000 68 e-13
- neutron-proton mass difference energy equivalent in MeV 1.293 332 17 0.000 000 42
- neutron-proton mass difference in u 0.001 388 449 19 0.000 000 000 45
- neutron-proton mass ratio 1.001 378 419 17 0.000 000 000 45
- neutron-tau mass ratio 0.528 790 0.000 048
- neutron to shielded proton mag. mom. ratio -0.684 996 94 0.000 000 16
- Newtonian constant of gravitation 6.673 84 e-11 0.000 80 e-11 m^3 kg^-1 s^-2
- Newtonian constant of gravitation over h-bar c 6.708 37 e-39 0.000 80 e-39 (GeV/c^2)^-2
- nuclear magneton 5.050 783 53 e-27 0.000 000 11 e-27 J T^-1
- nuclear magneton in eV/T 3.152 451 2605 e-8 0.000 000 0022 e-8 eV T^-1
- nuclear magneton in inverse meters per tesla 2.542 623 527 e-2 0.000 000 056 e-2 m^-1 T^-1
- nuclear magneton in K/T 3.658 2682 e-4 0.000 0033 e-4 K T^-1
- nuclear magneton in MHz/T 7.622 593 57 0.000 000 17 MHz T^-1
- Planck constant 6.626 069 57 e-34 0.000 000 29 e-34 J s
- Planck constant in eV s 4.135 667 516 e-15 0.000 000 091 e-15 eV s
- Planck constant over 2 pi 1.054 571 726 e-34 0.000 000 047 e-34 J s
- Planck constant over 2 pi in eV s 6.582 119 28 e-16 0.000 000 15 e-16 eV s
- Planck constant over 2 pi times c in MeV fm 197.326 9718 0.000 0044 MeV fm
- Planck length 1.616 199 e-35 0.000 097 e-35 m
- Planck mass 2.176 51 e-8 0.000 13 e-8 kg
- Planck mass energy equivalent in GeV 1.220 932 e19 0.000 073 e19 GeV
- Planck temperature 1.416 833 e32 0.000 085 e32 K
- Planck time 5.391 06 e-44 0.000 32 e-44 s
- proton charge to mass quotient 9.578 833 58 e7 0.000 000 21 e7 C kg^-1
- proton Compton wavelength 1.321 409 856 23 e-15 0.000 000 000 94 e-15 m
- proton Compton wavelength over 2 pi 0.210 308 910 47 e-15 0.000 000 000 15 e-15 m
- proton-electron mass ratio 1836.152 672 45 0.000 000 75
- proton g factor 5.585 694 713 0.000 000 046
- proton gyromag. ratio 2.675 222 005 e8 0.000 000 063 e8 s^-1 T^-1
- proton gyromag. ratio over 2 pi 42.577 4806 0.000 0010 MHz T^-1
- proton mag. mom. 1.410 606 743 e-26 0.000 000 033 e-26 J T^-1
- proton mag. mom. to Bohr magneton ratio 1.521 032 210 e-3 0.000 000 012 e-3
- proton mag. mom. to nuclear magneton ratio 2.792 847 356 0.000 000 023
- proton mag. shielding correction 25.694 e-6 0.014 e-6
- proton mass 1.672 621 777 e-27 0.000 000 074 e-27 kg
- proton mass energy equivalent 1.503 277 484 e-10 0.000 000 066 e-10 J
- proton mass energy equivalent in MeV 938.272 046 0.000 021 MeV
- proton mass in u 1.007 276 466 812 0.000 000 000 090 u
- proton molar mass 1.007 276 466 812 e-3 0.000 000 000 090 e-3 kg mol^-1
- proton-muon mass ratio 8.880 243 31 0.000 000 22
- proton-neutron mag. mom. ratio -1.459 898 06 0.000 000 34
- proton-neutron mass ratio 0.998 623 478 26 0.000 000 000 45
- proton rms charge radius 0.8775 e-15 0.0051 e-15 m
- proton-tau mass ratio 0.528 063 0.000 048
- quantum of circulation 3.636 947 5520 e-4 0.000 000 0024 e-4 m^2 s^-1
- quantum of circulation times 2 7.273 895 1040 e-4 0.000 000 0047 e-4 m^2 s^-1
- Rydberg constant 10 973 731.568 539 0.000 055 m^-1
- Rydberg constant times c in Hz 3.289 841 960 364 e15 0.000 000 000 017 e15 Hz
- Rydberg constant times hc in eV 13.605 692 53 0.000 000 30 eV
- Rydberg constant times hc in J 2.179 872 171 e-18 0.000 000 096 e-18 J
- Sackur-Tetrode constant (1 K, 100 kPa) -1.151 7078 0.000 0023
- Sackur-Tetrode constant (1 K, 101.325 kPa) -1.164 8708 0.000 0023
- second radiation constant 1.438 7770 e-2 0.000 0013 e-2 m K
- shielded helion gyromag. ratio 2.037 894 659 e8 0.000 000 051 e8 s^-1 T^-1
- shielded helion gyromag. ratio over 2 pi 32.434 100 84 0.000 000 81 MHz T^-1
- shielded helion mag. mom. -1.074 553 044 e-26 0.000 000 027 e-26 J T^-1
- shielded helion mag. mom. to Bohr magneton ratio -1.158 671 471 e-3 0.000 000 014 e-3
- shielded helion mag. mom. to nuclear magneton ratio -2.127 497 718 0.000 000 025
- shielded helion to proton mag. mom. ratio -0.761 766 558 0.000 000 011
- shielded helion to shielded proton mag. mom. ratio -0.761 786 1313 0.000 000 0033
- shielded proton gyromag. ratio 2.675 153 268 e8 0.000 000 066 e8 s^-1 T^-1
- shielded proton gyromag. ratio over 2 pi 42.576 3866 0.000 0010 MHz T^-1
- shielded proton mag. mom. 1.410 570 499 e-26 0.000 000 035 e-26 J T^-1
- shielded proton mag. mom. to Bohr magneton ratio 1.520 993 128 e-3 0.000 000 017 e-3
- shielded proton mag. mom. to nuclear magneton ratio 2.792 775 598 0.000 000 030
- speed of light in vacuum 299 792 458 (exact) m s^-1
- standard acceleration of gravity 9.806 65 (exact) m s^-2
- standard atmosphere 101 325 (exact) Pa
- standard-state pressure 100 000 (exact) Pa
- Stefan-Boltzmann constant 5.670 373 e-8 0.000 021 e-8 W m^-2 K^-4
- tau Compton wavelength 0.697 787 e-15 0.000 063 e-15 m
- tau Compton wavelength over 2 pi 0.111 056 e-15 0.000 010 e-15 m
- tau-electron mass ratio 3477.15 0.31
- tau mass 3.167 47 e-27 0.000 29 e-27 kg
- tau mass energy equivalent 2.846 78 e-10 0.000 26 e-10 J
- tau mass energy equivalent in MeV 1776.82 0.16 MeV
- tau mass in u 1.907 49 0.000 17 u
- tau molar mass 1.907 49 e-3 0.000 17 e-3 kg mol^-1
- tau-muon mass ratio 16.8167 0.0015
- tau-neutron mass ratio 1.891 11 0.000 17
- tau-proton mass ratio 1.893 72 0.000 17
- Thomson cross section 0.665 245 8734 e-28 0.000 000 0013 e-28 m^2
- triton-electron mass ratio 5496.921 5267 0.000 0050
- triton g factor 5.957 924 896 0.000 000 076
- triton mag. mom. 1.504 609 447 e-26 0.000 000 038 e-26 J T^-1
- triton mag. mom. to Bohr magneton ratio 1.622 393 657 e-3 0.000 000 021 e-3
- triton mag. mom. to nuclear magneton ratio 2.978 962 448 0.000 000 038
- triton mass 5.007 356 30 e-27 0.000 000 22 e-27 kg
- triton mass energy equivalent 4.500 387 41 e-10 0.000 000 20 e-10 J
- triton mass energy equivalent in MeV 2808.921 005 0.000 062 MeV
- triton mass in u 3.015 500 7134 0.000 000 0025 u
- triton molar mass 3.015 500 7134 e-3 0.000 000 0025 e-3 kg mol^-1
- triton-proton mass ratio 2.993 717 0308 0.000 000 0025
- unified atomic mass unit 1.660 538 921 e-27 0.000 000 073 e-27 kg
- von Klitzing constant 25 812.807 4434 0.000 0084 ohm
- weak mixing angle 0.2223 0.0021
- Wien frequency displacement law constant 5.878 9254 e10 0.000 0053 e10 Hz K^-1
- Wien wavelength displacement law constant 2.897 7721 e-3 0.000 0026 e-3 m K"""
- txt2014 = """\
- {220} lattice spacing of silicon 192.015 5714 e-12 0.000 0032 e-12 m
- alpha particle-electron mass ratio 7294.299 541 36 0.000 000 24
- alpha particle mass 6.644 657 230 e-27 0.000 000 082 e-27 kg
- alpha particle mass energy equivalent 5.971 920 097 e-10 0.000 000 073 e-10 J
- alpha particle mass energy equivalent in MeV 3727.379 378 0.000 023 MeV
- alpha particle mass in u 4.001 506 179 127 0.000 000 000 063 u
- alpha particle molar mass 4.001 506 179 127 e-3 0.000 000 000 063 e-3 kg mol^-1
- alpha particle-proton mass ratio 3.972 599 689 07 0.000 000 000 36
- Angstrom star 1.000 014 95 e-10 0.000 000 90 e-10 m
- atomic mass constant 1.660 539 040 e-27 0.000 000 020 e-27 kg
- atomic mass constant energy equivalent 1.492 418 062 e-10 0.000 000 018 e-10 J
- atomic mass constant energy equivalent in MeV 931.494 0954 0.000 0057 MeV
- atomic mass unit-electron volt relationship 931.494 0954 e6 0.000 0057 e6 eV
- atomic mass unit-hartree relationship 3.423 177 6902 e7 0.000 000 0016 e7 E_h
- atomic mass unit-hertz relationship 2.252 342 7206 e23 0.000 000 0010 e23 Hz
- atomic mass unit-inverse meter relationship 7.513 006 6166 e14 0.000 000 0034 e14 m^-1
- atomic mass unit-joule relationship 1.492 418 062 e-10 0.000 000 018 e-10 J
- atomic mass unit-kelvin relationship 1.080 954 38 e13 0.000 000 62 e13 K
- atomic mass unit-kilogram relationship 1.660 539 040 e-27 0.000 000 020 e-27 kg
- atomic unit of 1st hyperpolarizability 3.206 361 329 e-53 0.000 000 020 e-53 C^3 m^3 J^-2
- atomic unit of 2nd hyperpolarizability 6.235 380 085 e-65 0.000 000 077 e-65 C^4 m^4 J^-3
- atomic unit of action 1.054 571 800 e-34 0.000 000 013 e-34 J s
- atomic unit of charge 1.602 176 6208 e-19 0.000 000 0098 e-19 C
- atomic unit of charge density 1.081 202 3770 e12 0.000 000 0067 e12 C m^-3
- atomic unit of current 6.623 618 183 e-3 0.000 000 041 e-3 A
- atomic unit of electric dipole mom. 8.478 353 552 e-30 0.000 000 052 e-30 C m
- atomic unit of electric field 5.142 206 707 e11 0.000 000 032 e11 V m^-1
- atomic unit of electric field gradient 9.717 362 356 e21 0.000 000 060 e21 V m^-2
- atomic unit of electric polarizability 1.648 777 2731 e-41 0.000 000 0011 e-41 C^2 m^2 J^-1
- atomic unit of electric potential 27.211 386 02 0.000 000 17 V
- atomic unit of electric quadrupole mom. 4.486 551 484 e-40 0.000 000 028 e-40 C m^2
- atomic unit of energy 4.359 744 650 e-18 0.000 000 054 e-18 J
- atomic unit of force 8.238 723 36 e-8 0.000 000 10 e-8 N
- atomic unit of length 0.529 177 210 67 e-10 0.000 000 000 12 e-10 m
- atomic unit of mag. dipole mom. 1.854 801 999 e-23 0.000 000 011 e-23 J T^-1
- atomic unit of mag. flux density 2.350 517 550 e5 0.000 000 014 e5 T
- atomic unit of magnetizability 7.891 036 5886 e-29 0.000 000 0090 e-29 J T^-2
- atomic unit of mass 9.109 383 56 e-31 0.000 000 11 e-31 kg
- atomic unit of mom.um 1.992 851 882 e-24 0.000 000 024 e-24 kg m s^-1
- atomic unit of permittivity 1.112 650 056... e-10 (exact) F m^-1
- atomic unit of time 2.418 884 326509e-17 0.000 000 000014e-17 s
- atomic unit of velocity 2.187 691 262 77 e6 0.000 000 000 50 e6 m s^-1
- Avogadro constant 6.022 140 857 e23 0.000 000 074 e23 mol^-1
- Bohr magneton 927.400 9994 e-26 0.000 0057 e-26 J T^-1
- Bohr magneton in eV/T 5.788 381 8012 e-5 0.000 000 0026 e-5 eV T^-1
- Bohr magneton in Hz/T 13.996 245 042 e9 0.000 000 086 e9 Hz T^-1
- Bohr magneton in inverse meters per tesla 46.686 448 14 0.000 000 29 m^-1 T^-1
- Bohr magneton in K/T 0.671 714 05 0.000 000 39 K T^-1
- Bohr radius 0.529 177 210 67 e-10 0.000 000 000 12 e-10 m
- Boltzmann constant 1.380 648 52 e-23 0.000 000 79 e-23 J K^-1
- Boltzmann constant in eV/K 8.617 3303 e-5 0.000 0050 e-5 eV K^-1
- Boltzmann constant in Hz/K 2.083 6612 e10 0.000 0012 e10 Hz K^-1
- Boltzmann constant in inverse meters per kelvin 69.503 457 0.000 040 m^-1 K^-1
- characteristic impedance of vacuum 376.730 313 461... (exact) ohm
- classical electron radius 2.817 940 3227 e-15 0.000 000 0019 e-15 m
- Compton wavelength 2.426 310 2367 e-12 0.000 000 0011 e-12 m
- Compton wavelength over 2 pi 386.159 267 64 e-15 0.000 000 18 e-15 m
- conductance quantum 7.748 091 7310 e-5 0.000 000 0018 e-5 S
- conventional value of Josephson constant 483 597.9 e9 (exact) Hz V^-1
- conventional value of von Klitzing constant 25 812.807 (exact) ohm
- Cu x unit 1.002 076 97 e-13 0.000 000 28 e-13 m
- deuteron-electron mag. mom. ratio -4.664 345 535 e-4 0.000 000 026 e-4
- deuteron-electron mass ratio 3670.482 967 85 0.000 000 13
- deuteron g factor 0.857 438 2311 0.000 000 0048
- deuteron mag. mom. 0.433 073 5040 e-26 0.000 000 0036 e-26 J T^-1
- deuteron mag. mom. to Bohr magneton ratio 0.466 975 4554 e-3 0.000 000 0026 e-3
- deuteron mag. mom. to nuclear magneton ratio 0.857 438 2311 0.000 000 0048
- deuteron mass 3.343 583 719 e-27 0.000 000 041 e-27 kg
- deuteron mass energy equivalent 3.005 063 183 e-10 0.000 000 037 e-10 J
- deuteron mass energy equivalent in MeV 1875.612 928 0.000 012 MeV
- deuteron mass in u 2.013 553 212 745 0.000 000 000 040 u
- deuteron molar mass 2.013 553 212 745 e-3 0.000 000 000 040 e-3 kg mol^-1
- deuteron-neutron mag. mom. ratio -0.448 206 52 0.000 000 11
- deuteron-proton mag. mom. ratio 0.307 012 2077 0.000 000 0015
- deuteron-proton mass ratio 1.999 007 500 87 0.000 000 000 19
- deuteron rms charge radius 2.1413 e-15 0.0025 e-15 m
- electric constant 8.854 187 817... e-12 (exact) F m^-1
- electron charge to mass quotient -1.758 820 024 e11 0.000 000 011 e11 C kg^-1
- electron-deuteron mag. mom. ratio -2143.923 499 0.000 012
- electron-deuteron mass ratio 2.724 437 107 484 e-4 0.000 000 000 096 e-4
- electron g factor -2.002 319 304 361 82 0.000 000 000 000 52
- electron gyromag. ratio 1.760 859 644 e11 0.000 000 011 e11 s^-1 T^-1
- electron gyromag. ratio over 2 pi 28 024.951 64 0.000 17 MHz T^-1
- electron-helion mass ratio 1.819 543 074 854 e-4 0.000 000 000 088 e-4
- electron mag. mom. -928.476 4620 e-26 0.000 0057 e-26 J T^-1
- electron mag. mom. anomaly 1.159 652 180 91 e-3 0.000 000 000 26 e-3
- electron mag. mom. to Bohr magneton ratio -1.001 159 652 180 91 0.000 000 000 000 26
- electron mag. mom. to nuclear magneton ratio -1838.281 972 34 0.000 000 17
- electron mass 9.109 383 56 e-31 0.000 000 11 e-31 kg
- electron mass energy equivalent 8.187 105 65 e-14 0.000 000 10 e-14 J
- electron mass energy equivalent in MeV 0.510 998 9461 0.000 000 0031 MeV
- electron mass in u 5.485 799 090 70 e-4 0.000 000 000 16 e-4 u
- electron molar mass 5.485 799 090 70 e-7 0.000 000 000 16 e-7 kg mol^-1
- electron-muon mag. mom. ratio 206.766 9880 0.000 0046
- electron-muon mass ratio 4.836 331 70 e-3 0.000 000 11 e-3
- electron-neutron mag. mom. ratio 960.920 50 0.000 23
- electron-neutron mass ratio 5.438 673 4428 e-4 0.000 000 0027 e-4
- electron-proton mag. mom. ratio -658.210 6866 0.000 0020
- electron-proton mass ratio 5.446 170 213 52 e-4 0.000 000 000 52 e-4
- electron-tau mass ratio 2.875 92 e-4 0.000 26 e-4
- electron to alpha particle mass ratio 1.370 933 554 798 e-4 0.000 000 000 045 e-4
- electron to shielded helion mag. mom. ratio 864.058 257 0.000 010
- electron to shielded proton mag. mom. ratio -658.227 5971 0.000 0072
- electron-triton mass ratio 1.819 200 062 203 e-4 0.000 000 000 084 e-4
- electron volt 1.602 176 6208 e-19 0.000 000 0098 e-19 J
- electron volt-atomic mass unit relationship 1.073 544 1105 e-9 0.000 000 0066 e-9 u
- electron volt-hartree relationship 3.674 932 248 e-2 0.000 000 023 e-2 E_h
- electron volt-hertz relationship 2.417 989 262 e14 0.000 000 015 e14 Hz
- electron volt-inverse meter relationship 8.065 544 005 e5 0.000 000 050 e5 m^-1
- electron volt-joule relationship 1.602 176 6208 e-19 0.000 000 0098 e-19 J
- electron volt-kelvin relationship 1.160 452 21 e4 0.000 000 67 e4 K
- electron volt-kilogram relationship 1.782 661 907 e-36 0.000 000 011 e-36 kg
- elementary charge 1.602 176 6208 e-19 0.000 000 0098 e-19 C
- elementary charge over h 2.417 989 262 e14 0.000 000 015 e14 A J^-1
- Faraday constant 96 485.332 89 0.000 59 C mol^-1
- Faraday constant for conventional electric current 96 485.3251 0.0012 C_90 mol^-1
- Fermi coupling constant 1.166 3787 e-5 0.000 0006 e-5 GeV^-2
- fine-structure constant 7.297 352 5664 e-3 0.000 000 0017 e-3
- first radiation constant 3.741 771 790 e-16 0.000 000 046 e-16 W m^2
- first radiation constant for spectral radiance 1.191 042 953 e-16 0.000 000 015 e-16 W m^2 sr^-1
- hartree-atomic mass unit relationship 2.921 262 3197 e-8 0.000 000 0013 e-8 u
- hartree-electron volt relationship 27.211 386 02 0.000 000 17 eV
- Hartree energy 4.359 744 650 e-18 0.000 000 054 e-18 J
- Hartree energy in eV 27.211 386 02 0.000 000 17 eV
- hartree-hertz relationship 6.579 683 920 711 e15 0.000 000 000 039 e15 Hz
- hartree-inverse meter relationship 2.194 746 313 702 e7 0.000 000 000 013 e7 m^-1
- hartree-joule relationship 4.359 744 650 e-18 0.000 000 054 e-18 J
- hartree-kelvin relationship 3.157 7513 e5 0.000 0018 e5 K
- hartree-kilogram relationship 4.850 870 129 e-35 0.000 000 060 e-35 kg
- helion-electron mass ratio 5495.885 279 22 0.000 000 27
- helion g factor -4.255 250 616 0.000 000 050
- helion mag. mom. -1.074 617 522 e-26 0.000 000 014 e-26 J T^-1
- helion mag. mom. to Bohr magneton ratio -1.158 740 958 e-3 0.000 000 014 e-3
- helion mag. mom. to nuclear magneton ratio -2.127 625 308 0.000 000 025
- helion mass 5.006 412 700 e-27 0.000 000 062 e-27 kg
- helion mass energy equivalent 4.499 539 341 e-10 0.000 000 055 e-10 J
- helion mass energy equivalent in MeV 2808.391 586 0.000 017 MeV
- helion mass in u 3.014 932 246 73 0.000 000 000 12 u
- helion molar mass 3.014 932 246 73 e-3 0.000 000 000 12 e-3 kg mol^-1
- helion-proton mass ratio 2.993 152 670 46 0.000 000 000 29
- hertz-atomic mass unit relationship 4.439 821 6616 e-24 0.000 000 0020 e-24 u
- hertz-electron volt relationship 4.135 667 662 e-15 0.000 000 025 e-15 eV
- hertz-hartree relationship 1.5198298460088 e-16 0.0000000000090e-16 E_h
- hertz-inverse meter relationship 3.335 640 951... e-9 (exact) m^-1
- hertz-joule relationship 6.626 070 040 e-34 0.000 000 081 e-34 J
- hertz-kelvin relationship 4.799 2447 e-11 0.000 0028 e-11 K
- hertz-kilogram relationship 7.372 497 201 e-51 0.000 000 091 e-51 kg
- inverse fine-structure constant 137.035 999 139 0.000 000 031
- inverse meter-atomic mass unit relationship 1.331 025 049 00 e-15 0.000 000 000 61 e-15 u
- inverse meter-electron volt relationship 1.239 841 9739 e-6 0.000 000 0076 e-6 eV
- inverse meter-hartree relationship 4.556 335 252 767 e-8 0.000 000 000 027 e-8 E_h
- inverse meter-hertz relationship 299 792 458 (exact) Hz
- inverse meter-joule relationship 1.986 445 824 e-25 0.000 000 024 e-25 J
- inverse meter-kelvin relationship 1.438 777 36 e-2 0.000 000 83 e-2 K
- inverse meter-kilogram relationship 2.210 219 057 e-42 0.000 000 027 e-42 kg
- inverse of conductance quantum 12 906.403 7278 0.000 0029 ohm
- Josephson constant 483 597.8525 e9 0.0030 e9 Hz V^-1
- joule-atomic mass unit relationship 6.700 535 363 e9 0.000 000 082 e9 u
- joule-electron volt relationship 6.241 509 126 e18 0.000 000 038 e18 eV
- joule-hartree relationship 2.293 712 317 e17 0.000 000 028 e17 E_h
- joule-hertz relationship 1.509 190 205 e33 0.000 000 019 e33 Hz
- joule-inverse meter relationship 5.034 116 651 e24 0.000 000 062 e24 m^-1
- joule-kelvin relationship 7.242 9731 e22 0.000 0042 e22 K
- joule-kilogram relationship 1.112 650 056... e-17 (exact) kg
- kelvin-atomic mass unit relationship 9.251 0842 e-14 0.000 0053 e-14 u
- kelvin-electron volt relationship 8.617 3303 e-5 0.000 0050 e-5 eV
- kelvin-hartree relationship 3.166 8105 e-6 0.000 0018 e-6 E_h
- kelvin-hertz relationship 2.083 6612 e10 0.000 0012 e10 Hz
- kelvin-inverse meter relationship 69.503 457 0.000 040 m^-1
- kelvin-joule relationship 1.380 648 52 e-23 0.000 000 79 e-23 J
- kelvin-kilogram relationship 1.536 178 65 e-40 0.000 000 88 e-40 kg
- kilogram-atomic mass unit relationship 6.022 140 857 e26 0.000 000 074 e26 u
- kilogram-electron volt relationship 5.609 588 650 e35 0.000 000 034 e35 eV
- kilogram-hartree relationship 2.061 485 823 e34 0.000 000 025 e34 E_h
- kilogram-hertz relationship 1.356 392 512 e50 0.000 000 017 e50 Hz
- kilogram-inverse meter relationship 4.524 438 411 e41 0.000 000 056 e41 m^-1
- kilogram-joule relationship 8.987 551 787... e16 (exact) J
- kilogram-kelvin relationship 6.509 6595 e39 0.000 0037 e39 K
- lattice parameter of silicon 543.102 0504 e-12 0.000 0089 e-12 m
- Loschmidt constant (273.15 K, 100 kPa) 2.651 6467 e25 0.000 0015 e25 m^-3
- Loschmidt constant (273.15 K, 101.325 kPa) 2.686 7811 e25 0.000 0015 e25 m^-3
- mag. constant 12.566 370 614... e-7 (exact) N A^-2
- mag. flux quantum 2.067 833 831 e-15 0.000 000 013 e-15 Wb
- molar gas constant 8.314 4598 0.000 0048 J mol^-1 K^-1
- molar mass constant 1 e-3 (exact) kg mol^-1
- molar mass of carbon-12 12 e-3 (exact) kg mol^-1
- molar Planck constant 3.990 312 7110 e-10 0.000 000 0018 e-10 J s mol^-1
- molar Planck constant times c 0.119 626 565 582 0.000 000 000 054 J m mol^-1
- molar volume of ideal gas (273.15 K, 100 kPa) 22.710 947 e-3 0.000 013 e-3 m^3 mol^-1
- molar volume of ideal gas (273.15 K, 101.325 kPa) 22.413 962 e-3 0.000 013 e-3 m^3 mol^-1
- molar volume of silicon 12.058 832 14 e-6 0.000 000 61 e-6 m^3 mol^-1
- Mo x unit 1.002 099 52 e-13 0.000 000 53 e-13 m
- muon Compton wavelength 11.734 441 11 e-15 0.000 000 26 e-15 m
- muon Compton wavelength over 2 pi 1.867 594 308 e-15 0.000 000 042 e-15 m
- muon-electron mass ratio 206.768 2826 0.000 0046
- muon g factor -2.002 331 8418 0.000 000 0013
- muon mag. mom. -4.490 448 26 e-26 0.000 000 10 e-26 J T^-1
- muon mag. mom. anomaly 1.165 920 89 e-3 0.000 000 63 e-3
- muon mag. mom. to Bohr magneton ratio -4.841 970 48 e-3 0.000 000 11 e-3
- muon mag. mom. to nuclear magneton ratio -8.890 597 05 0.000 000 20
- muon mass 1.883 531 594 e-28 0.000 000 048 e-28 kg
- muon mass energy equivalent 1.692 833 774 e-11 0.000 000 043 e-11 J
- muon mass energy equivalent in MeV 105.658 3745 0.000 0024 MeV
- muon mass in u 0.113 428 9257 0.000 000 0025 u
- muon molar mass 0.113 428 9257 e-3 0.000 000 0025 e-3 kg mol^-1
- muon-neutron mass ratio 0.112 454 5167 0.000 000 0025
- muon-proton mag. mom. ratio -3.183 345 142 0.000 000 071
- muon-proton mass ratio 0.112 609 5262 0.000 000 0025
- muon-tau mass ratio 5.946 49 e-2 0.000 54 e-2
- natural unit of action 1.054 571 800 e-34 0.000 000 013 e-34 J s
- natural unit of action in eV s 6.582 119 514 e-16 0.000 000 040 e-16 eV s
- natural unit of energy 8.187 105 65 e-14 0.000 000 10 e-14 J
- natural unit of energy in MeV 0.510 998 9461 0.000 000 0031 MeV
- natural unit of length 386.159 267 64 e-15 0.000 000 18 e-15 m
- natural unit of mass 9.109 383 56 e-31 0.000 000 11 e-31 kg
- natural unit of mom.um 2.730 924 488 e-22 0.000 000 034 e-22 kg m s^-1
- natural unit of mom.um in MeV/c 0.510 998 9461 0.000 000 0031 MeV/c
- natural unit of time 1.288 088 667 12 e-21 0.000 000 000 58 e-21 s
- natural unit of velocity 299 792 458 (exact) m s^-1
- neutron Compton wavelength 1.319 590 904 81 e-15 0.000 000 000 88 e-15 m
- neutron Compton wavelength over 2 pi 0.210 019 415 36 e-15 0.000 000 000 14 e-15 m
- neutron-electron mag. mom. ratio 1.040 668 82 e-3 0.000 000 25 e-3
- neutron-electron mass ratio 1838.683 661 58 0.000 000 90
- neutron g factor -3.826 085 45 0.000 000 90
- neutron gyromag. ratio 1.832 471 72 e8 0.000 000 43 e8 s^-1 T^-1
- neutron gyromag. ratio over 2 pi 29.164 6933 0.000 0069 MHz T^-1
- neutron mag. mom. -0.966 236 50 e-26 0.000 000 23 e-26 J T^-1
- neutron mag. mom. to Bohr magneton ratio -1.041 875 63 e-3 0.000 000 25 e-3
- neutron mag. mom. to nuclear magneton ratio -1.913 042 73 0.000 000 45
- neutron mass 1.674 927 471 e-27 0.000 000 021 e-27 kg
- neutron mass energy equivalent 1.505 349 739 e-10 0.000 000 019 e-10 J
- neutron mass energy equivalent in MeV 939.565 4133 0.000 0058 MeV
- neutron mass in u 1.008 664 915 88 0.000 000 000 49 u
- neutron molar mass 1.008 664 915 88 e-3 0.000 000 000 49 e-3 kg mol^-1
- neutron-muon mass ratio 8.892 484 08 0.000 000 20
- neutron-proton mag. mom. ratio -0.684 979 34 0.000 000 16
- neutron-proton mass difference 2.305 573 77 e-30 0.000 000 85 e-30
- neutron-proton mass difference energy equivalent 2.072 146 37 e-13 0.000 000 76 e-13
- neutron-proton mass difference energy equivalent in MeV 1.293 332 05 0.000 000 48
- neutron-proton mass difference in u 0.001 388 449 00 0.000 000 000 51
- neutron-proton mass ratio 1.001 378 418 98 0.000 000 000 51
- neutron-tau mass ratio 0.528 790 0.000 048
- neutron to shielded proton mag. mom. ratio -0.684 996 94 0.000 000 16
- Newtonian constant of gravitation 6.674 08 e-11 0.000 31 e-11 m^3 kg^-1 s^-2
- Newtonian constant of gravitation over h-bar c 6.708 61 e-39 0.000 31 e-39 (GeV/c^2)^-2
- nuclear magneton 5.050 783 699 e-27 0.000 000 031 e-27 J T^-1
- nuclear magneton in eV/T 3.152 451 2550 e-8 0.000 000 0015 e-8 eV T^-1
- nuclear magneton in inverse meters per tesla 2.542 623 432 e-2 0.000 000 016 e-2 m^-1 T^-1
- nuclear magneton in K/T 3.658 2690 e-4 0.000 0021 e-4 K T^-1
- nuclear magneton in MHz/T 7.622 593 285 0.000 000 047 MHz T^-1
- Planck constant 6.626 070 040 e-34 0.000 000 081 e-34 J s
- Planck constant in eV s 4.135 667 662 e-15 0.000 000 025 e-15 eV s
- Planck constant over 2 pi 1.054 571 800 e-34 0.000 000 013 e-34 J s
- Planck constant over 2 pi in eV s 6.582 119 514 e-16 0.000 000 040 e-16 eV s
- Planck constant over 2 pi times c in MeV fm 197.326 9788 0.000 0012 MeV fm
- Planck length 1.616 229 e-35 0.000 038 e-35 m
- Planck mass 2.176 470 e-8 0.000 051 e-8 kg
- Planck mass energy equivalent in GeV 1.220 910 e19 0.000 029 e19 GeV
- Planck temperature 1.416 808 e32 0.000 033 e32 K
- Planck time 5.391 16 e-44 0.000 13 e-44 s
- proton charge to mass quotient 9.578 833 226 e7 0.000 000 059 e7 C kg^-1
- proton Compton wavelength 1.321 409 853 96 e-15 0.000 000 000 61 e-15 m
- proton Compton wavelength over 2 pi 0.210 308910109e-15 0.000 000 000097e-15 m
- proton-electron mass ratio 1836.152 673 89 0.000 000 17
- proton g factor 5.585 694 702 0.000 000 017
- proton gyromag. ratio 2.675 221 900 e8 0.000 000 018 e8 s^-1 T^-1
- proton gyromag. ratio over 2 pi 42.577 478 92 0.000 000 29 MHz T^-1
- proton mag. mom. 1.410 606 7873 e-26 0.000 000 0097 e-26 J T^-1
- proton mag. mom. to Bohr magneton ratio 1.521 032 2053 e-3 0.000 000 0046 e-3
- proton mag. mom. to nuclear magneton ratio 2.792 847 3508 0.000 000 0085
- proton mag. shielding correction 25.691 e-6 0.011 e-6
- proton mass 1.672 621 898 e-27 0.000 000 021 e-27 kg
- proton mass energy equivalent 1.503 277 593 e-10 0.000 000 018 e-10 J
- proton mass energy equivalent in MeV 938.272 0813 0.000 0058 MeV
- proton mass in u 1.007 276 466 879 0.000 000 000 091 u
- proton molar mass 1.007 276 466 879 e-3 0.000 000 000 091 e-3 kg mol^-1
- proton-muon mass ratio 8.880 243 38 0.000 000 20
- proton-neutron mag. mom. ratio -1.459 898 05 0.000 000 34
- proton-neutron mass ratio 0.998 623 478 44 0.000 000 000 51
- proton rms charge radius 0.8751 e-15 0.0061 e-15 m
- proton-tau mass ratio 0.528 063 0.000 048
- quantum of circulation 3.636 947 5486 e-4 0.000 000 0017 e-4 m^2 s^-1
- quantum of circulation times 2 7.273 895 0972 e-4 0.000 000 0033 e-4 m^2 s^-1
- Rydberg constant 10 973 731.568 508 0.000 065 m^-1
- Rydberg constant times c in Hz 3.289 841 960 355 e15 0.000 000 000 019 e15 Hz
- Rydberg constant times hc in eV 13.605 693 009 0.000 000 084 eV
- Rydberg constant times hc in J 2.179 872 325 e-18 0.000 000 027 e-18 J
- Sackur-Tetrode constant (1 K, 100 kPa) -1.151 7084 0.000 0014
- Sackur-Tetrode constant (1 K, 101.325 kPa) -1.164 8714 0.000 0014
- second radiation constant 1.438 777 36 e-2 0.000 000 83 e-2 m K
- shielded helion gyromag. ratio 2.037 894 585 e8 0.000 000 027 e8 s^-1 T^-1
- shielded helion gyromag. ratio over 2 pi 32.434 099 66 0.000 000 43 MHz T^-1
- shielded helion mag. mom. -1.074 553 080 e-26 0.000 000 014 e-26 J T^-1
- shielded helion mag. mom. to Bohr magneton ratio -1.158 671 471 e-3 0.000 000 014 e-3
- shielded helion mag. mom. to nuclear magneton ratio -2.127 497 720 0.000 000 025
- shielded helion to proton mag. mom. ratio -0.761 766 5603 0.000 000 0092
- shielded helion to shielded proton mag. mom. ratio -0.761 786 1313 0.000 000 0033
- shielded proton gyromag. ratio 2.675 153 171 e8 0.000 000 033 e8 s^-1 T^-1
- shielded proton gyromag. ratio over 2 pi 42.576 385 07 0.000 000 53 MHz T^-1
- shielded proton mag. mom. 1.410 570 547 e-26 0.000 000 018 e-26 J T^-1
- shielded proton mag. mom. to Bohr magneton ratio 1.520 993 128 e-3 0.000 000 017 e-3
- shielded proton mag. mom. to nuclear magneton ratio 2.792 775 600 0.000 000 030
- speed of light in vacuum 299 792 458 (exact) m s^-1
- standard acceleration of gravity 9.806 65 (exact) m s^-2
- standard atmosphere 101 325 (exact) Pa
- standard-state pressure 100 000 (exact) Pa
- Stefan-Boltzmann constant 5.670 367 e-8 0.000 013 e-8 W m^-2 K^-4
- tau Compton wavelength 0.697 787 e-15 0.000 063 e-15 m
- tau Compton wavelength over 2 pi 0.111 056 e-15 0.000 010 e-15 m
- tau-electron mass ratio 3477.15 0.31
- tau mass 3.167 47 e-27 0.000 29 e-27 kg
- tau mass energy equivalent 2.846 78 e-10 0.000 26 e-10 J
- tau mass energy equivalent in MeV 1776.82 0.16 MeV
- tau mass in u 1.907 49 0.000 17 u
- tau molar mass 1.907 49 e-3 0.000 17 e-3 kg mol^-1
- tau-muon mass ratio 16.8167 0.0015
- tau-neutron mass ratio 1.891 11 0.000 17
- tau-proton mass ratio 1.893 72 0.000 17
- Thomson cross section 0.665 245 871 58 e-28 0.000 000 000 91 e-28 m^2
- triton-electron mass ratio 5496.921 535 88 0.000 000 26
- triton g factor 5.957 924 920 0.000 000 028
- triton mag. mom. 1.504 609 503 e-26 0.000 000 012 e-26 J T^-1
- triton mag. mom. to Bohr magneton ratio 1.622 393 6616 e-3 0.000 000 0076 e-3
- triton mag. mom. to nuclear magneton ratio 2.978 962 460 0.000 000 014
- triton mass 5.007 356 665 e-27 0.000 000 062 e-27 kg
- triton mass energy equivalent 4.500 387 735 e-10 0.000 000 055 e-10 J
- triton mass energy equivalent in MeV 2808.921 112 0.000 017 MeV
- triton mass in u 3.015 500 716 32 0.000 000 000 11 u
- triton molar mass 3.015 500 716 32 e-3 0.000 000 000 11 e-3 kg mol^-1
- triton-proton mass ratio 2.993 717 033 48 0.000 000 000 22
- unified atomic mass unit 1.660 539 040 e-27 0.000 000 020 e-27 kg
- von Klitzing constant 25 812.807 4555 0.000 0059 ohm
- weak mixing angle 0.2223 0.0021
- Wien frequency displacement law constant 5.878 9238 e10 0.000 0034 e10 Hz K^-1
- Wien wavelength displacement law constant 2.897 7729 e-3 0.000 0017 e-3 m K"""
- txt2018 = """\
- alpha particle-electron mass ratio 7294.299 541 42 0.000 000 24
- alpha particle mass 6.644 657 3357 e-27 0.000 000 0020 e-27 kg
- alpha particle mass energy equivalent 5.971 920 1914 e-10 0.000 000 0018 e-10 J
- alpha particle mass energy equivalent in MeV 3727.379 4066 0.000 0011 MeV
- alpha particle mass in u 4.001 506 179 127 0.000 000 000 063 u
- alpha particle molar mass 4.001 506 1777 e-3 0.000 000 0012 e-3 kg mol^-1
- alpha particle-proton mass ratio 3.972 599 690 09 0.000 000 000 22
- alpha particle relative atomic mass 4.001 506 179 127 0.000 000 000 063
- Angstrom star 1.000 014 95 e-10 0.000 000 90 e-10 m
- atomic mass constant 1.660 539 066 60 e-27 0.000 000 000 50 e-27 kg
- atomic mass constant energy equivalent 1.492 418 085 60 e-10 0.000 000 000 45 e-10 J
- atomic mass constant energy equivalent in MeV 931.494 102 42 0.000 000 28 MeV
- atomic mass unit-electron volt relationship 9.314 941 0242 e8 0.000 000 0028 e8 eV
- atomic mass unit-hartree relationship 3.423 177 6874 e7 0.000 000 0010 e7 E_h
- atomic mass unit-hertz relationship 2.252 342 718 71 e23 0.000 000 000 68 e23 Hz
- atomic mass unit-inverse meter relationship 7.513 006 6104 e14 0.000 000 0023 e14 m^-1
- atomic mass unit-joule relationship 1.492 418 085 60 e-10 0.000 000 000 45 e-10 J
- atomic mass unit-kelvin relationship 1.080 954 019 16 e13 0.000 000 000 33 e13 K
- atomic mass unit-kilogram relationship 1.660 539 066 60 e-27 0.000 000 000 50 e-27 kg
- atomic unit of 1st hyperpolarizability 3.206 361 3061 e-53 0.000 000 0015 e-53 C^3 m^3 J^-2
- atomic unit of 2nd hyperpolarizability 6.235 379 9905 e-65 0.000 000 0038 e-65 C^4 m^4 J^-3
- atomic unit of action 1.054 571 817... e-34 (exact) J s
- atomic unit of charge 1.602 176 634 e-19 (exact) C
- atomic unit of charge density 1.081 202 384 57 e12 0.000 000 000 49 e12 C m^-3
- atomic unit of current 6.623 618 237 510 e-3 0.000 000 000 013 e-3 A
- atomic unit of electric dipole mom. 8.478 353 6255 e-30 0.000 000 0013 e-30 C m
- atomic unit of electric field 5.142 206 747 63 e11 0.000 000 000 78 e11 V m^-1
- atomic unit of electric field gradient 9.717 362 4292 e21 0.000 000 0029 e21 V m^-2
- atomic unit of electric polarizability 1.648 777 274 36 e-41 0.000 000 000 50 e-41 C^2 m^2 J^-1
- atomic unit of electric potential 27.211 386 245 988 0.000 000 000 053 V
- atomic unit of electric quadrupole mom. 4.486 551 5246 e-40 0.000 000 0014 e-40 C m^2
- atomic unit of energy 4.359 744 722 2071 e-18 0.000 000 000 0085 e-18 J
- atomic unit of force 8.238 723 4983 e-8 0.000 000 0012 e-8 N
- atomic unit of length 5.291 772 109 03 e-11 0.000 000 000 80 e-11 m
- atomic unit of mag. dipole mom. 1.854 802 015 66 e-23 0.000 000 000 56 e-23 J T^-1
- atomic unit of mag. flux density 2.350 517 567 58 e5 0.000 000 000 71 e5 T
- atomic unit of magnetizability 7.891 036 6008 e-29 0.000 000 0048 e-29 J T^-2
- atomic unit of mass 9.109 383 7015 e-31 0.000 000 0028 e-31 kg
- atomic unit of momentum 1.992 851 914 10 e-24 0.000 000 000 30 e-24 kg m s^-1
- atomic unit of permittivity 1.112 650 055 45 e-10 0.000 000 000 17 e-10 F m^-1
- atomic unit of time 2.418 884 326 5857 e-17 0.000 000 000 0047 e-17 s
- atomic unit of velocity 2.187 691 263 64 e6 0.000 000 000 33 e6 m s^-1
- Avogadro constant 6.022 140 76 e23 (exact) mol^-1
- Bohr magneton 9.274 010 0783 e-24 0.000 000 0028 e-24 J T^-1
- Bohr magneton in eV/T 5.788 381 8060 e-5 0.000 000 0017 e-5 eV T^-1
- Bohr magneton in Hz/T 1.399 624 493 61 e10 0.000 000 000 42 e10 Hz T^-1
- Bohr magneton in inverse meter per tesla 46.686 447 783 0.000 000 014 m^-1 T^-1
- Bohr magneton in K/T 0.671 713 815 63 0.000 000 000 20 K T^-1
- Bohr radius 5.291 772 109 03 e-11 0.000 000 000 80 e-11 m
- Boltzmann constant 1.380 649 e-23 (exact) J K^-1
- Boltzmann constant in eV/K 8.617 333 262... e-5 (exact) eV K^-1
- Boltzmann constant in Hz/K 2.083 661 912... e10 (exact) Hz K^-1
- Boltzmann constant in inverse meter per kelvin 69.503 480 04... (exact) m^-1 K^-1
- classical electron radius 2.817 940 3262 e-15 0.000 000 0013 e-15 m
- Compton wavelength 2.426 310 238 67 e-12 0.000 000 000 73 e-12 m
- conductance quantum 7.748 091 729... e-5 (exact) S
- conventional value of ampere-90 1.000 000 088 87... (exact) A
- conventional value of coulomb-90 1.000 000 088 87... (exact) C
- conventional value of farad-90 0.999 999 982 20... (exact) F
- conventional value of henry-90 1.000 000 017 79... (exact) H
- conventional value of Josephson constant 483 597.9 e9 (exact) Hz V^-1
- conventional value of ohm-90 1.000 000 017 79... (exact) ohm
- conventional value of volt-90 1.000 000 106 66... (exact) V
- conventional value of von Klitzing constant 25 812.807 (exact) ohm
- conventional value of watt-90 1.000 000 195 53... (exact) W
- Cu x unit 1.002 076 97 e-13 0.000 000 28 e-13 m
- deuteron-electron mag. mom. ratio -4.664 345 551 e-4 0.000 000 012 e-4
- deuteron-electron mass ratio 3670.482 967 88 0.000 000 13
- deuteron g factor 0.857 438 2338 0.000 000 0022
- deuteron mag. mom. 4.330 735 094 e-27 0.000 000 011 e-27 J T^-1
- deuteron mag. mom. to Bohr magneton ratio 4.669 754 570 e-4 0.000 000 012 e-4
- deuteron mag. mom. to nuclear magneton ratio 0.857 438 2338 0.000 000 0022
- deuteron mass 3.343 583 7724 e-27 0.000 000 0010 e-27 kg
- deuteron mass energy equivalent 3.005 063 231 02 e-10 0.000 000 000 91 e-10 J
- deuteron mass energy equivalent in MeV 1875.612 942 57 0.000 000 57 MeV
- deuteron mass in u 2.013 553 212 745 0.000 000 000 040 u
- deuteron molar mass 2.013 553 212 05 e-3 0.000 000 000 61 e-3 kg mol^-1
- deuteron-neutron mag. mom. ratio -0.448 206 53 0.000 000 11
- deuteron-proton mag. mom. ratio 0.307 012 209 39 0.000 000 000 79
- deuteron-proton mass ratio 1.999 007 501 39 0.000 000 000 11
- deuteron relative atomic mass 2.013 553 212 745 0.000 000 000 040
- deuteron rms charge radius 2.127 99 e-15 0.000 74 e-15 m
- electron charge to mass quotient -1.758 820 010 76 e11 0.000 000 000 53 e11 C kg^-1
- electron-deuteron mag. mom. ratio -2143.923 4915 0.000 0056
- electron-deuteron mass ratio 2.724 437 107 462 e-4 0.000 000 000 096 e-4
- electron g factor -2.002 319 304 362 56 0.000 000 000 000 35
- electron gyromag. ratio 1.760 859 630 23 e11 0.000 000 000 53 e11 s^-1 T^-1
- electron gyromag. ratio in MHz/T 28 024.951 4242 0.000 0085 MHz T^-1
- electron-helion mass ratio 1.819 543 074 573 e-4 0.000 000 000 079 e-4
- electron mag. mom. -9.284 764 7043 e-24 0.000 000 0028 e-24 J T^-1
- electron mag. mom. anomaly 1.159 652 181 28 e-3 0.000 000 000 18 e-3
- electron mag. mom. to Bohr magneton ratio -1.001 159 652 181 28 0.000 000 000 000 18
- electron mag. mom. to nuclear magneton ratio -1838.281 971 88 0.000 000 11
- electron mass 9.109 383 7015 e-31 0.000 000 0028 e-31 kg
- electron mass energy equivalent 8.187 105 7769 e-14 0.000 000 0025 e-14 J
- electron mass energy equivalent in MeV 0.510 998 950 00 0.000 000 000 15 MeV
- electron mass in u 5.485 799 090 65 e-4 0.000 000 000 16 e-4 u
- electron molar mass 5.485 799 0888 e-7 0.000 000 0017 e-7 kg mol^-1
- electron-muon mag. mom. ratio 206.766 9883 0.000 0046
- electron-muon mass ratio 4.836 331 69 e-3 0.000 000 11 e-3
- electron-neutron mag. mom. ratio 960.920 50 0.000 23
- electron-neutron mass ratio 5.438 673 4424 e-4 0.000 000 0026 e-4
- electron-proton mag. mom. ratio -658.210 687 89 0.000 000 20
- electron-proton mass ratio 5.446 170 214 87 e-4 0.000 000 000 33 e-4
- electron relative atomic mass 5.485 799 090 65 e-4 0.000 000 000 16 e-4
- electron-tau mass ratio 2.875 85 e-4 0.000 19 e-4
- electron to alpha particle mass ratio 1.370 933 554 787 e-4 0.000 000 000 045 e-4
- electron to shielded helion mag. mom. ratio 864.058 257 0.000 010
- electron to shielded proton mag. mom. ratio -658.227 5971 0.000 0072
- electron-triton mass ratio 1.819 200 062 251 e-4 0.000 000 000 090 e-4
- electron volt 1.602 176 634 e-19 (exact) J
- electron volt-atomic mass unit relationship 1.073 544 102 33 e-9 0.000 000 000 32 e-9 u
- electron volt-hartree relationship 3.674 932 217 5655 e-2 0.000 000 000 0071 e-2 E_h
- electron volt-hertz relationship 2.417 989 242... e14 (exact) Hz
- electron volt-inverse meter relationship 8.065 543 937... e5 (exact) m^-1
- electron volt-joule relationship 1.602 176 634 e-19 (exact) J
- electron volt-kelvin relationship 1.160 451 812... e4 (exact) K
- electron volt-kilogram relationship 1.782 661 921... e-36 (exact) kg
- elementary charge 1.602 176 634 e-19 (exact) C
- elementary charge over h-bar 1.519 267 447... e15 (exact) A J^-1
- Faraday constant 96 485.332 12... (exact) C mol^-1
- Fermi coupling constant 1.166 3787 e-5 0.000 0006 e-5 GeV^-2
- fine-structure constant 7.297 352 5693 e-3 0.000 000 0011 e-3
- first radiation constant 3.741 771 852... e-16 (exact) W m^2
- first radiation constant for spectral radiance 1.191 042 972... e-16 (exact) W m^2 sr^-1
- hartree-atomic mass unit relationship 2.921 262 322 05 e-8 0.000 000 000 88 e-8 u
- hartree-electron volt relationship 27.211 386 245 988 0.000 000 000 053 eV
- Hartree energy 4.359 744 722 2071 e-18 0.000 000 000 0085 e-18 J
- Hartree energy in eV 27.211 386 245 988 0.000 000 000 053 eV
- hartree-hertz relationship 6.579 683 920 502 e15 0.000 000 000 013 e15 Hz
- hartree-inverse meter relationship 2.194 746 313 6320 e7 0.000 000 000 0043 e7 m^-1
- hartree-joule relationship 4.359 744 722 2071 e-18 0.000 000 000 0085 e-18 J
- hartree-kelvin relationship 3.157 750 248 0407 e5 0.000 000 000 0061 e5 K
- hartree-kilogram relationship 4.850 870 209 5432 e-35 0.000 000 000 0094 e-35 kg
- helion-electron mass ratio 5495.885 280 07 0.000 000 24
- helion g factor -4.255 250 615 0.000 000 050
- helion mag. mom. -1.074 617 532 e-26 0.000 000 013 e-26 J T^-1
- helion mag. mom. to Bohr magneton ratio -1.158 740 958 e-3 0.000 000 014 e-3
- helion mag. mom. to nuclear magneton ratio -2.127 625 307 0.000 000 025
- helion mass 5.006 412 7796 e-27 0.000 000 0015 e-27 kg
- helion mass energy equivalent 4.499 539 4125 e-10 0.000 000 0014 e-10 J
- helion mass energy equivalent in MeV 2808.391 607 43 0.000 000 85 MeV
- helion mass in u 3.014 932 247 175 0.000 000 000 097 u
- helion molar mass 3.014 932 246 13 e-3 0.000 000 000 91 e-3 kg mol^-1
- helion-proton mass ratio 2.993 152 671 67 0.000 000 000 13
- helion relative atomic mass 3.014 932 247 175 0.000 000 000 097
- helion shielding shift 5.996 743 e-5 0.000 010 e-5
- hertz-atomic mass unit relationship 4.439 821 6652 e-24 0.000 000 0013 e-24 u
- hertz-electron volt relationship 4.135 667 696... e-15 (exact) eV
- hertz-hartree relationship 1.519 829 846 0570 e-16 0.000 000 000 0029 e-16 E_h
- hertz-inverse meter relationship 3.335 640 951... e-9 (exact) m^-1
- hertz-joule relationship 6.626 070 15 e-34 (exact) J
- hertz-kelvin relationship 4.799 243 073... e-11 (exact) K
- hertz-kilogram relationship 7.372 497 323... e-51 (exact) kg
- hyperfine transition frequency of Cs-133 9 192 631 770 (exact) Hz
- inverse fine-structure constant 137.035 999 084 0.000 000 021
- inverse meter-atomic mass unit relationship 1.331 025 050 10 e-15 0.000 000 000 40 e-15 u
- inverse meter-electron volt relationship 1.239 841 984... e-6 (exact) eV
- inverse meter-hartree relationship 4.556 335 252 9120 e-8 0.000 000 000 0088 e-8 E_h
- inverse meter-hertz relationship 299 792 458 (exact) Hz
- inverse meter-joule relationship 1.986 445 857... e-25 (exact) J
- inverse meter-kelvin relationship 1.438 776 877... e-2 (exact) K
- inverse meter-kilogram relationship 2.210 219 094... e-42 (exact) kg
- inverse of conductance quantum 12 906.403 72... (exact) ohm
- Josephson constant 483 597.848 4... e9 (exact) Hz V^-1
- joule-atomic mass unit relationship 6.700 535 2565 e9 0.000 000 0020 e9 u
- joule-electron volt relationship 6.241 509 074... e18 (exact) eV
- joule-hartree relationship 2.293 712 278 3963 e17 0.000 000 000 0045 e17 E_h
- joule-hertz relationship 1.509 190 179... e33 (exact) Hz
- joule-inverse meter relationship 5.034 116 567... e24 (exact) m^-1
- joule-kelvin relationship 7.242 970 516... e22 (exact) K
- joule-kilogram relationship 1.112 650 056... e-17 (exact) kg
- kelvin-atomic mass unit relationship 9.251 087 3014 e-14 0.000 000 0028 e-14 u
- kelvin-electron volt relationship 8.617 333 262... e-5 (exact) eV
- kelvin-hartree relationship 3.166 811 563 4556 e-6 0.000 000 000 0061 e-6 E_h
- kelvin-hertz relationship 2.083 661 912... e10 (exact) Hz
- kelvin-inverse meter relationship 69.503 480 04... (exact) m^-1
- kelvin-joule relationship 1.380 649 e-23 (exact) J
- kelvin-kilogram relationship 1.536 179 187... e-40 (exact) kg
- kilogram-atomic mass unit relationship 6.022 140 7621 e26 0.000 000 0018 e26 u
- kilogram-electron volt relationship 5.609 588 603... e35 (exact) eV
- kilogram-hartree relationship 2.061 485 788 7409 e34 0.000 000 000 0040 e34 E_h
- kilogram-hertz relationship 1.356 392 489... e50 (exact) Hz
- kilogram-inverse meter relationship 4.524 438 335... e41 (exact) m^-1
- kilogram-joule relationship 8.987 551 787... e16 (exact) J
- kilogram-kelvin relationship 6.509 657 260... e39 (exact) K
- lattice parameter of silicon 5.431 020 511 e-10 0.000 000 089 e-10 m
- lattice spacing of ideal Si (220) 1.920 155 716 e-10 0.000 000 032 e-10 m
- Loschmidt constant (273.15 K, 100 kPa) 2.651 645 804... e25 (exact) m^-3
- Loschmidt constant (273.15 K, 101.325 kPa) 2.686 780 111... e25 (exact) m^-3
- luminous efficacy 683 (exact) lm W^-1
- mag. flux quantum 2.067 833 848... e-15 (exact) Wb
- molar gas constant 8.314 462 618... (exact) J mol^-1 K^-1
- molar mass constant 0.999 999 999 65 e-3 0.000 000 000 30 e-3 kg mol^-1
- molar mass of carbon-12 11.999 999 9958 e-3 0.000 000 0036 e-3 kg mol^-1
- molar Planck constant 3.990 312 712... e-10 (exact) J Hz^-1 mol^-1
- molar volume of ideal gas (273.15 K, 100 kPa) 22.710 954 64... e-3 (exact) m^3 mol^-1
- molar volume of ideal gas (273.15 K, 101.325 kPa) 22.413 969 54... e-3 (exact) m^3 mol^-1
- molar volume of silicon 1.205 883 199 e-5 0.000 000 060 e-5 m^3 mol^-1
- Mo x unit 1.002 099 52 e-13 0.000 000 53 e-13 m
- muon Compton wavelength 1.173 444 110 e-14 0.000 000 026 e-14 m
- muon-electron mass ratio 206.768 2830 0.000 0046
- muon g factor -2.002 331 8418 0.000 000 0013
- muon mag. mom. -4.490 448 30 e-26 0.000 000 10 e-26 J T^-1
- muon mag. mom. anomaly 1.165 920 89 e-3 0.000 000 63 e-3
- muon mag. mom. to Bohr magneton ratio -4.841 970 47 e-3 0.000 000 11 e-3
- muon mag. mom. to nuclear magneton ratio -8.890 597 03 0.000 000 20
- muon mass 1.883 531 627 e-28 0.000 000 042 e-28 kg
- muon mass energy equivalent 1.692 833 804 e-11 0.000 000 038 e-11 J
- muon mass energy equivalent in MeV 105.658 3755 0.000 0023 MeV
- muon mass in u 0.113 428 9259 0.000 000 0025 u
- muon molar mass 1.134 289 259 e-4 0.000 000 025 e-4 kg mol^-1
- muon-neutron mass ratio 0.112 454 5170 0.000 000 0025
- muon-proton mag. mom. ratio -3.183 345 142 0.000 000 071
- muon-proton mass ratio 0.112 609 5264 0.000 000 0025
- muon-tau mass ratio 5.946 35 e-2 0.000 40 e-2
- natural unit of action 1.054 571 817... e-34 (exact) J s
- natural unit of action in eV s 6.582 119 569... e-16 (exact) eV s
- natural unit of energy 8.187 105 7769 e-14 0.000 000 0025 e-14 J
- natural unit of energy in MeV 0.510 998 950 00 0.000 000 000 15 MeV
- natural unit of length 3.861 592 6796 e-13 0.000 000 0012 e-13 m
- natural unit of mass 9.109 383 7015 e-31 0.000 000 0028 e-31 kg
- natural unit of momentum 2.730 924 530 75 e-22 0.000 000 000 82 e-22 kg m s^-1
- natural unit of momentum in MeV/c 0.510 998 950 00 0.000 000 000 15 MeV/c
- natural unit of time 1.288 088 668 19 e-21 0.000 000 000 39 e-21 s
- natural unit of velocity 299 792 458 (exact) m s^-1
- neutron Compton wavelength 1.319 590 905 81 e-15 0.000 000 000 75 e-15 m
- neutron-electron mag. mom. ratio 1.040 668 82 e-3 0.000 000 25 e-3
- neutron-electron mass ratio 1838.683 661 73 0.000 000 89
- neutron g factor -3.826 085 45 0.000 000 90
- neutron gyromag. ratio 1.832 471 71 e8 0.000 000 43 e8 s^-1 T^-1
- neutron gyromag. ratio in MHz/T 29.164 6931 0.000 0069 MHz T^-1
- neutron mag. mom. -9.662 3651 e-27 0.000 0023 e-27 J T^-1
- neutron mag. mom. to Bohr magneton ratio -1.041 875 63 e-3 0.000 000 25 e-3
- neutron mag. mom. to nuclear magneton ratio -1.913 042 73 0.000 000 45
- neutron mass 1.674 927 498 04 e-27 0.000 000 000 95 e-27 kg
- neutron mass energy equivalent 1.505 349 762 87 e-10 0.000 000 000 86 e-10 J
- neutron mass energy equivalent in MeV 939.565 420 52 0.000 000 54 MeV
- neutron mass in u 1.008 664 915 95 0.000 000 000 49 u
- neutron molar mass 1.008 664 915 60 e-3 0.000 000 000 57 e-3 kg mol^-1
- neutron-muon mass ratio 8.892 484 06 0.000 000 20
- neutron-proton mag. mom. ratio -0.684 979 34 0.000 000 16
- neutron-proton mass difference 2.305 574 35 e-30 0.000 000 82 e-30 kg
- neutron-proton mass difference energy equivalent 2.072 146 89 e-13 0.000 000 74 e-13 J
- neutron-proton mass difference energy equivalent in MeV 1.293 332 36 0.000 000 46 MeV
- neutron-proton mass difference in u 1.388 449 33 e-3 0.000 000 49 e-3 u
- neutron-proton mass ratio 1.001 378 419 31 0.000 000 000 49
- neutron relative atomic mass 1.008 664 915 95 0.000 000 000 49
- neutron-tau mass ratio 0.528 779 0.000 036
- neutron to shielded proton mag. mom. ratio -0.684 996 94 0.000 000 16
- Newtonian constant of gravitation 6.674 30 e-11 0.000 15 e-11 m^3 kg^-1 s^-2
- Newtonian constant of gravitation over h-bar c 6.708 83 e-39 0.000 15 e-39 (GeV/c^2)^-2
- nuclear magneton 5.050 783 7461 e-27 0.000 000 0015 e-27 J T^-1
- nuclear magneton in eV/T 3.152 451 258 44 e-8 0.000 000 000 96 e-8 eV T^-1
- nuclear magneton in inverse meter per tesla 2.542 623 413 53 e-2 0.000 000 000 78 e-2 m^-1 T^-1
- nuclear magneton in K/T 3.658 267 7756 e-4 0.000 000 0011 e-4 K T^-1
- nuclear magneton in MHz/T 7.622 593 2291 0.000 000 0023 MHz T^-1
- Planck constant 6.626 070 15 e-34 (exact) J Hz^-1
- Planck constant in eV/Hz 4.135 667 696... e-15 (exact) eV Hz^-1
- Planck length 1.616 255 e-35 0.000 018 e-35 m
- Planck mass 2.176 434 e-8 0.000 024 e-8 kg
- Planck mass energy equivalent in GeV 1.220 890 e19 0.000 014 e19 GeV
- Planck temperature 1.416 784 e32 0.000 016 e32 K
- Planck time 5.391 247 e-44 0.000 060 e-44 s
- proton charge to mass quotient 9.578 833 1560 e7 0.000 000 0029 e7 C kg^-1
- proton Compton wavelength 1.321 409 855 39 e-15 0.000 000 000 40 e-15 m
- proton-electron mass ratio 1836.152 673 43 0.000 000 11
- proton g factor 5.585 694 6893 0.000 000 0016
- proton gyromag. ratio 2.675 221 8744 e8 0.000 000 0011 e8 s^-1 T^-1
- proton gyromag. ratio in MHz/T 42.577 478 518 0.000 000 018 MHz T^-1
- proton mag. mom. 1.410 606 797 36 e-26 0.000 000 000 60 e-26 J T^-1
- proton mag. mom. to Bohr magneton ratio 1.521 032 202 30 e-3 0.000 000 000 46 e-3
- proton mag. mom. to nuclear magneton ratio 2.792 847 344 63 0.000 000 000 82
- proton mag. shielding correction 2.5689 e-5 0.0011 e-5
- proton mass 1.672 621 923 69 e-27 0.000 000 000 51 e-27 kg
- proton mass energy equivalent 1.503 277 615 98 e-10 0.000 000 000 46 e-10 J
- proton mass energy equivalent in MeV 938.272 088 16 0.000 000 29 MeV
- proton mass in u 1.007 276 466 621 0.000 000 000 053 u
- proton molar mass 1.007 276 466 27 e-3 0.000 000 000 31 e-3 kg mol^-1
- proton-muon mass ratio 8.880 243 37 0.000 000 20
- proton-neutron mag. mom. ratio -1.459 898 05 0.000 000 34
- proton-neutron mass ratio 0.998 623 478 12 0.000 000 000 49
- proton relative atomic mass 1.007 276 466 621 0.000 000 000 053
- proton rms charge radius 8.414 e-16 0.019 e-16 m
- proton-tau mass ratio 0.528 051 0.000 036
- quantum of circulation 3.636 947 5516 e-4 0.000 000 0011 e-4 m^2 s^-1
- quantum of circulation times 2 7.273 895 1032 e-4 0.000 000 0022 e-4 m^2 s^-1
- reduced Compton wavelength 3.861 592 6796 e-13 0.000 000 0012 e-13 m
- reduced muon Compton wavelength 1.867 594 306 e-15 0.000 000 042 e-15 m
- reduced neutron Compton wavelength 2.100 194 1552 e-16 0.000 000 0012 e-16 m
- reduced Planck constant 1.054 571 817... e-34 (exact) J s
- reduced Planck constant in eV s 6.582 119 569... e-16 (exact) eV s
- reduced Planck constant times c in MeV fm 197.326 980 4... (exact) MeV fm
- reduced proton Compton wavelength 2.103 089 103 36 e-16 0.000 000 000 64 e-16 m
- reduced tau Compton wavelength 1.110 538 e-16 0.000 075 e-16 m
- Rydberg constant 10 973 731.568 160 0.000 021 m^-1
- Rydberg constant times c in Hz 3.289 841 960 2508 e15 0.000 000 000 0064 e15 Hz
- Rydberg constant times hc in eV 13.605 693 122 994 0.000 000 000 026 eV
- Rydberg constant times hc in J 2.179 872 361 1035 e-18 0.000 000 000 0042 e-18 J
- Sackur-Tetrode constant (1 K, 100 kPa) -1.151 707 537 06 0.000 000 000 45
- Sackur-Tetrode constant (1 K, 101.325 kPa) -1.164 870 523 58 0.000 000 000 45
- second radiation constant 1.438 776 877... e-2 (exact) m K
- shielded helion gyromag. ratio 2.037 894 569 e8 0.000 000 024 e8 s^-1 T^-1
- shielded helion gyromag. ratio in MHz/T 32.434 099 42 0.000 000 38 MHz T^-1
- shielded helion mag. mom. -1.074 553 090 e-26 0.000 000 013 e-26 J T^-1
- shielded helion mag. mom. to Bohr magneton ratio -1.158 671 471 e-3 0.000 000 014 e-3
- shielded helion mag. mom. to nuclear magneton ratio -2.127 497 719 0.000 000 025
- shielded helion to proton mag. mom. ratio -0.761 766 5618 0.000 000 0089
- shielded helion to shielded proton mag. mom. ratio -0.761 786 1313 0.000 000 0033
- shielded proton gyromag. ratio 2.675 153 151 e8 0.000 000 029 e8 s^-1 T^-1
- shielded proton gyromag. ratio in MHz/T 42.576 384 74 0.000 000 46 MHz T^-1
- shielded proton mag. mom. 1.410 570 560 e-26 0.000 000 015 e-26 J T^-1
- shielded proton mag. mom. to Bohr magneton ratio 1.520 993 128 e-3 0.000 000 017 e-3
- shielded proton mag. mom. to nuclear magneton ratio 2.792 775 599 0.000 000 030
- shielding difference of d and p in HD 2.0200 e-8 0.0020 e-8
- shielding difference of t and p in HT 2.4140 e-8 0.0020 e-8
- speed of light in vacuum 299 792 458 (exact) m s^-1
- standard acceleration of gravity 9.806 65 (exact) m s^-2
- standard atmosphere 101 325 (exact) Pa
- standard-state pressure 100 000 (exact) Pa
- Stefan-Boltzmann constant 5.670 374 419... e-8 (exact) W m^-2 K^-4
- tau Compton wavelength 6.977 71 e-16 0.000 47 e-16 m
- tau-electron mass ratio 3477.23 0.23
- tau energy equivalent 1776.86 0.12 MeV
- tau mass 3.167 54 e-27 0.000 21 e-27 kg
- tau mass energy equivalent 2.846 84 e-10 0.000 19 e-10 J
- tau mass in u 1.907 54 0.000 13 u
- tau molar mass 1.907 54 e-3 0.000 13 e-3 kg mol^-1
- tau-muon mass ratio 16.8170 0.0011
- tau-neutron mass ratio 1.891 15 0.000 13
- tau-proton mass ratio 1.893 76 0.000 13
- Thomson cross section 6.652 458 7321 e-29 0.000 000 0060 e-29 m^2
- triton-electron mass ratio 5496.921 535 73 0.000 000 27
- triton g factor 5.957 924 931 0.000 000 012
- triton mag. mom. 1.504 609 5202 e-26 0.000 000 0030 e-26 J T^-1
- triton mag. mom. to Bohr magneton ratio 1.622 393 6651 e-3 0.000 000 0032 e-3
- triton mag. mom. to nuclear magneton ratio 2.978 962 4656 0.000 000 0059
- triton mass 5.007 356 7446 e-27 0.000 000 0015 e-27 kg
- triton mass energy equivalent 4.500 387 8060 e-10 0.000 000 0014 e-10 J
- triton mass energy equivalent in MeV 2808.921 132 98 0.000 000 85 MeV
- triton mass in u 3.015 500 716 21 0.000 000 000 12 u
- triton molar mass 3.015 500 715 17 e-3 0.000 000 000 92 e-3 kg mol^-1
- triton-proton mass ratio 2.993 717 034 14 0.000 000 000 15
- triton relative atomic mass 3.015 500 716 21 0.000 000 000 12
- triton to proton mag. mom. ratio 1.066 639 9191 0.000 000 0021
- unified atomic mass unit 1.660 539 066 60 e-27 0.000 000 000 50 e-27 kg
- vacuum electric permittivity 8.854 187 8128 e-12 0.000 000 0013 e-12 F m^-1
- vacuum mag. permeability 1.256 637 062 12 e-6 0.000 000 000 19 e-6 N A^-2
- von Klitzing constant 25 812.807 45... (exact) ohm
- weak mixing angle 0.222 90 0.000 30
- Wien frequency displacement law constant 5.878 925 757... e10 (exact) Hz K^-1
- Wien wavelength displacement law constant 2.897 771 955... e-3 (exact) m K
- W to Z mass ratio 0.881 53 0.000 17 """
- # -----------------------------------------------------------------------------
- physical_constants: dict[str, tuple[float, str, float]] = {}
- def parse_constants_2002to2014(d: str) -> dict[str, tuple[float, str, float]]:
- constants = {}
- for line in d.split('\n'):
- name = line[:55].rstrip()
- val = float(line[55:77].replace(' ', '').replace('...', ''))
- uncert = float(line[77:99].replace(' ', '').replace('(exact)', '0'))
- units = line[99:].rstrip()
- constants[name] = (val, units, uncert)
- return constants
- def parse_constants_2018toXXXX(d: str) -> dict[str, tuple[float, str, float]]:
- constants = {}
- for line in d.split('\n'):
- name = line[:60].rstrip()
- val = float(line[60:85].replace(' ', '').replace('...', ''))
- uncert = float(line[85:110].replace(' ', '').replace('(exact)', '0'))
- units = line[110:].rstrip()
- constants[name] = (val, units, uncert)
- return constants
- _physical_constants_2002 = parse_constants_2002to2014(txt2002)
- _physical_constants_2006 = parse_constants_2002to2014(txt2006)
- _physical_constants_2010 = parse_constants_2002to2014(txt2010)
- _physical_constants_2014 = parse_constants_2002to2014(txt2014)
- _physical_constants_2018 = parse_constants_2018toXXXX(txt2018)
- physical_constants.update(_physical_constants_2002)
- physical_constants.update(_physical_constants_2006)
- physical_constants.update(_physical_constants_2010)
- physical_constants.update(_physical_constants_2014)
- physical_constants.update(_physical_constants_2018)
- _current_constants = _physical_constants_2018
- _current_codata = "CODATA 2018"
- # check obsolete values
- _obsolete_constants = {}
- for k in physical_constants:
- if k not in _current_constants:
- _obsolete_constants[k] = True
- # generate some additional aliases
- _aliases = {}
- for k in _physical_constants_2002:
- if 'magn.' in k:
- _aliases[k] = k.replace('magn.', 'mag.')
- for k in _physical_constants_2006:
- if 'momentum' in k:
- _aliases[k] = k.replace('momentum', 'mom.um')
- for k in _physical_constants_2018:
- if 'momentum' in k:
- _aliases[k] = k.replace('momentum', 'mom.um')
- # CODATA 2018: renamed and no longer exact; use as aliases
- _aliases['mag. constant'] = 'vacuum mag. permeability'
- _aliases['electric constant'] = 'vacuum electric permittivity'
- class ConstantWarning(DeprecationWarning):
- """Accessing a constant no longer in current CODATA data set"""
- pass
- def _check_obsolete(key: str) -> None:
- if key in _obsolete_constants and key not in _aliases:
- warnings.warn("Constant '%s' is not in current %s data set" % (
- key, _current_codata), ConstantWarning)
- def value(key: str) -> float:
- """
- Value in physical_constants indexed by key
- Parameters
- ----------
- key : Python string
- Key in dictionary `physical_constants`
- Returns
- -------
- value : float
- Value in `physical_constants` corresponding to `key`
- Examples
- --------
- >>> from scipy import constants
- >>> constants.value('elementary charge')
- 1.602176634e-19
- """
- _check_obsolete(key)
- return physical_constants[key][0]
- def unit(key: str) -> str:
- """
- Unit in physical_constants indexed by key
- Parameters
- ----------
- key : Python string
- Key in dictionary `physical_constants`
- Returns
- -------
- unit : Python string
- Unit in `physical_constants` corresponding to `key`
- Examples
- --------
- >>> from scipy import constants
- >>> constants.unit('proton mass')
- 'kg'
- """
- _check_obsolete(key)
- return physical_constants[key][1]
- def precision(key: str) -> float:
- """
- Relative precision in physical_constants indexed by key
- Parameters
- ----------
- key : Python string
- Key in dictionary `physical_constants`
- Returns
- -------
- prec : float
- Relative precision in `physical_constants` corresponding to `key`
- Examples
- --------
- >>> from scipy import constants
- >>> constants.precision('proton mass')
- 5.1e-37
- """
- _check_obsolete(key)
- return physical_constants[key][2] / physical_constants[key][0]
- def find(sub: str | None = None, disp: bool = False) -> Any:
- """
- Return list of physical_constant keys containing a given string.
- Parameters
- ----------
- sub : str
- Sub-string to search keys for. By default, return all keys.
- disp : bool
- If True, print the keys that are found and return None.
- Otherwise, return the list of keys without printing anything.
- Returns
- -------
- keys : list or None
- If `disp` is False, the list of keys is returned.
- Otherwise, None is returned.
- Examples
- --------
- >>> from scipy.constants import find, physical_constants
- Which keys in the ``physical_constants`` dictionary contain 'boltzmann'?
- >>> find('boltzmann')
- ['Boltzmann constant',
- 'Boltzmann constant in Hz/K',
- 'Boltzmann constant in eV/K',
- 'Boltzmann constant in inverse meter per kelvin',
- 'Stefan-Boltzmann constant']
- Get the constant called 'Boltzmann constant in Hz/K':
- >>> physical_constants['Boltzmann constant in Hz/K']
- (20836619120.0, 'Hz K^-1', 0.0)
- Find constants with 'radius' in the key:
- >>> find('radius')
- ['Bohr radius',
- 'classical electron radius',
- 'deuteron rms charge radius',
- 'proton rms charge radius']
- >>> physical_constants['classical electron radius']
- (2.8179403262e-15, 'm', 1.3e-24)
- """
- if sub is None:
- result = list(_current_constants.keys())
- else:
- result = [key for key in _current_constants
- if sub.lower() in key.lower()]
- result.sort()
- if disp:
- for key in result:
- print(key)
- return
- else:
- return result
- c = value('speed of light in vacuum')
- mu0 = value('vacuum mag. permeability')
- epsilon0 = value('vacuum electric permittivity')
- # Table is lacking some digits for exact values: calculate from definition
- exact_values = {
- 'joule-kilogram relationship': (1 / (c * c), 'kg', 0.0),
- 'kilogram-joule relationship': (c * c, 'J', 0.0),
- 'hertz-inverse meter relationship': (1 / c, 'm^-1', 0.0),
- # The following derived quantities are no longer exact (CODATA2018):
- # specify separately
- 'characteristic impedance of vacuum': (
- sqrt(mu0 / epsilon0), 'ohm',
- sqrt(mu0 / epsilon0) * 0.5 * (
- physical_constants['vacuum mag. permeability'][2] / mu0
- + physical_constants['vacuum electric permittivity'][2] / epsilon0))
- }
- # sanity check
- for key in exact_values:
- val = physical_constants[key][0]
- if abs(exact_values[key][0] - val) / val > 1e-9:
- raise ValueError("Constants.codata: exact values too far off.")
- if exact_values[key][2] == 0 and physical_constants[key][2] != 0:
- raise ValueError("Constants.codata: value not exact")
- physical_constants.update(exact_values)
- _tested_keys = ['natural unit of velocity',
- 'natural unit of action',
- 'natural unit of action in eV s',
- 'natural unit of mass',
- 'natural unit of energy',
- 'natural unit of energy in MeV',
- 'natural unit of mom.um',
- 'natural unit of mom.um in MeV/c',
- 'natural unit of length',
- 'natural unit of time']
- # finally, insert aliases for values
- for k, v in list(_aliases.items()):
- if v in _current_constants or v in _tested_keys:
- physical_constants[k] = physical_constants[v]
- else:
- del _aliases[k]
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