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Name Symbol Value
atomic mass constant mu 1.660539x10-27 kg
Avogadro constant NA 6.022142x1023 /mol
Bohr magneton mB 9.274009x10-24 J/T
Bohr radius a0 5.291772x10-11 m
Boltzmann constant k 1.380650x10-23 J/K
conductance quantum G0 7.748092x10-5 S
electric permittivity constant e0 1/(m0·c2) = 8.85418781...x10-12 F/m
electron Compton wavelength lc 2.426310x10-12 m
electron magnetic moment me 9.284764x10-24
electron radius (classical) re 2.817940x10-15 m
electron rest mass me 9.109382x10-31 kg
electron volt eV 1.602176x10-19 J
elementary charge e 1.602176x10-19 C
Euler's constant g 0.577215664901532...
Faraday constant F 9.648524x104 C/mol
fine-structure constant a 7.297353x10-3
first radiation constant c1 3.741771x10-16 W/m2
golden ratio f 1.618033988749894...
gravitational constant G 6.6732x10-11 N-m2/kg2
Josephson constant KJ 4.835979x1014 Hz/V
magnetic flux quantum F0 2.067834x10-15 Wb
magnetic permeability constant m0 4p x10-7 = 1.2566370614...x10-6 H/m
natural log base e 2.718281828459045...
neutron magnetic moment mn 9.662364x10-27 J/T
neutron rest mass mn 1.674927x10-27 kg
nuclear magneton mN 5.050783x10-27 J/T
pi p 3.14159265358979323846264...
Planck constant h 6.626069x10-34 J-s
proton Compton wavelength lc,p 1.321410x10-15 m
proton magnetic moment mp 1.410607x10-26 J/T
proton rest mass mp 1.672622x10-27 kg
Rydberg constant 1.097373x107 /m
second radiation constant c2 1.438775x10-2 m-K
speed of light in vacuum c 2.99792458x108 m/s
standard volume of ideal gas V0 2.24136x10-2 m3/mol
Stefan-Boltzmann constant s 5.670400x10-8 W/m2-K4
universal gas constant R 8.314472 J/mol-K
Wien displacement law constant b 2.897769x10-3 m-K