# |
Constant |
Symbol |
Value |
Units |
1 |
Speed of light in vacuum |
(c) |
299792458 |
m s-1 |
2 |
Permeability of vacuum |
(mu_0) |
1.25663706143592e-06 |
N A-2 |
3 |
Permittivity of vacuum |
(epsilon_0) |
8.854187817e-12 |
F m-1 |
4 |
Newtonian constant of gravitation |
(G) |
6.67259e-11 ± 8.5e-15 |
m3 kg-1 s-2 |
5 |
Planck constant |
(h) |
6.6260755e-34 ± 4.0e-40 |
J s |
6 |
Planck constant in eV |
|
4.1356692e-15 ± 1.2e-21 |
eV s |
7 |
h-bar |
(h-bar) |
1.05457266e-34 ± 6.3e-41 |
J s |
8 |
h-bar in eV |
|
6.582122e-16 ± 2.0e-22 |
eV s |
9 |
Planck mass |
(m_p) |
2.17671e-08 ± 1.4e-12 |
kg |
10 |
Planck length |
(l_p) |
1.61605e-35 ± 1.0e-39 |
m |
11 |
Planck time |
(t_p) |
5.39056e-44 ± 3.4e-48 |
s |
12 |
Elementary charge |
(e) |
1.60217733e-19 ± 4.9e-26 |
C |
13 |
Magnetic flux quantum |
(Phi_0) |
2.06783461e-15 ± 6.1e-22 |
Wb |
14 |
Josephson frequency-voltage quotient |
|
483597670000000 ± 1.4e+08 |
V-1 s-1 |
15 |
Quantized Hall conductance |
|
3.87404614e-05 ± 1.7e-12 |
Omega-1 |
16 |
Quantized Hall resistance |
(R_H) |
25812.8056 ± 0.0012 |
Omega |
17 |
Bohr magneton |
(mu_B) |
9.2740154e-24 ± 3.1e-30 |
J T-1 |
18 |
Bohr magneton in eV |
|
5.78838263e-05 ± 5.2e-12 |
eV T-1 |
19 |
Bohr magneton in Hz |
|
13996241800 ± 4200 |
T-1 s-1 |
20 |
Bohr magneton in wavenumbers |
|
46.686437 ± 1.4e-05 |
m-1 T-1 |
21 |
Bohr magneton in kelvins |
|
0.6717099 ± 5.7e-06 |
K T-1 |
22 |
Nuclear magneton |
(mu_N) |
5.0507866e-27 ± 1.7e-33 |
J T-1 |
23 |
Nuclear magneton in eV |
|
3.15245166e-08 ± 2.8e-15 |
eV T-1 |
24 |
Nuclear magneton in Hz |
|
7622591.4 ± 2.3 |
T-1 s-1 |
25 |
Nuclear magneton in wavenumbers |
|
0.0254262281 ± 7.7e-09 |
m-1 T-1 |
26 |
Nuclear magneton in kelvins |
|
0.0003658246 ± 3.1e-09 |
K T-1 |
27 |
Fine structure constant |
(alpha) |
0.00729735308 ± 3.3e-10 |
|
28 |
Inverse fine structure constant |
|
137.0359895 ± 6.1e-06 |
|
29 |
Rydberg constant |
(Ry) |
10973731.534 ± 0.013 |
m-1 |
30 |
Rydberg constant in Hz |
|
3.2898419499e+15 ± 3.9e+06 |
s-1 |
31 |
Rydberg constant in joules |
|
2.1798741e-18 ± 1.3e-24 |
J |
32 |
Rydberg constant in eV |
|
13.6056981 ± 4.0e-06 |
eV |
33 |
Bohr radius |
(a_0) |
5.29177249e-11 ± 2.4e-18 |
m |
34 |
Hartree energy |
(E_h) |
4.3597482e-18 ± 2.6e-24 |
J |
35 |
Hartree energy in eV |
|
27.2113961 ± 8.1e-06 |
eV |
36 |
Quantum of circulation |
|
0.000363694807 ± 3.3e-11 |
m2 s-1 |
37 |
Electron mass |
(m_e) |
9.1093897e-31 ± 5.4e-37 |
kg |
38 |
Electron mass in u |
|
0.000548579903 ± 1.3e-11 |
u |
39 |
Electron mass in eV |
|
510999.06 ± 0.15 |
eV |
40 |
Electron-muon mass ratio |
|
0.00483633218 ± 7.1e-10 |
|
41 |
Electron-proton mass ratio |
|
0.000544617013 ± 1.1e-11 |
|
42 |
Electron-deuteron mass ratio |
|
0.000272443707 ± 6e-12 |
|
43 |
Electron-alpha-particle mass ratio |
|
0.000137093354 ± 3e-12 |
|
44 |
Electron specific charge |
|
-175881962000 ± -53000 |
C kg-1 |
45 |
Electron molar mass |
|
5.48579903e-07 ± 1.3e-14 |
kg mol-1 |
46 |
Electron Compton wavelength |
(lambda_C) |
2.42631058e-12 ± 2.2e-19 |
m |
47 |
Electron Compton wavelength over 2 pi |
(lambda-bar_C) |
3.86159323e-13 ± 3.5e-20 |
m |
48 |
Electron classical radius |
(r_e) |
2.81794092e-15 ± 3.8e-22 |
m |
49 |
Electron Thomson cross section |
(sigma_e) |
6.6524616e-29 ± 1.8e-35 |
m2 |
50 |
Electron magnetic moment |
|
9.2847701e-24 ± 3.1e-30 |
J T-1 |
51 |
Electron magnetic moment in Bohr magnetons |
|
1.001159652193 ± 1.0e-11 |
|
52 |
Electron magnetic moment in nuclear magnetons |
|
1838.282 ± 3.7e-05 |
|
53 |
Electron magnetic moment anomaly |
(a_e) |
0.001159652193 ± 1.0e-11 |
|
54 |
Electron g-factor |
(g_e) |
2.002319304386 ± 2.0e-11 |
|
55 |
Electron-muon magnetic moment ratio |
|
206.766967 ± 3.0e-05 |
|
56 |
Electron-proton magnetic moment ratio |
|
658.2106881 ± 6.6e-06 |
|
57 |
Muon mass |
|
1.8835327e-28 ± 1.1e-34 |
kg |
58 |
Muon mass in u |
|
0.113428913 ± 1.7e-08 |
u |
59 |
Muon mass in eV |
|
105658389 ± 34 |
eV |
60 |
Muon-electron mass ratio |
|
206.768262 ± 3.0e-05 |
|
61 |
Muon molar mass |
|
0.000113428913 ± 1.7e-11 |
kg mol-1 |
62 |
Muon magnetic moment |
|
4.4904514e-26 ± 1.5e-32 |
J T-1 |
63 |
Muon magnetic moment in Bohr magnetons |
|
0.00484197097 ± 7.1e-10 |
|
64 |
Muon magnetic moment in nuclear magnetons |
|
8.8905981 ± 1.3e-06 |
|
65 |
Muon magnetic moment anomaly |
(a_mu) |
0.001165923 ± 8.4e-09 |
|
66 |
Muon g-factor |
(g_mu) |
2.002331846 ± 1.7e-08 |
|
67 |
Muon-proton magnetic moment ratio |
|
3.18334547 ± 4.7e-07 |
|
68 |
Proton mass |
(m_p) |
1.6726231e-27 ± 1.0e-33 |
kg |
69 |
Proton mass in u |
|
1.00727647 ± 1.2e-08 |
u |
70 |
Proton mass in eV |
|
938272310 ± 280 |
eV |
71 |
Proton-electron mass ratio |
|
1836.152701 ± 3.7e-05 |
|
72 |
Proton-muon mass ratio |
|
8.8802444 ± 1.3e-06 |
|
73 |
Proton specific charge |
|
95788309 ± 29 |
C kg-1 |
74 |
Proton molar mass |
|
0.00100727647 ± 1.2e-11 |
kg mol-1 |
75 |
Proton Compton wavelength |
(lambda_C,p) |
1.32141002e-15 ± 1.2e-22 |
m |
76 |
Proton magnetic moment |
|
1.41060761e-26 ± 4.7e-33 |
J T-1 |
77 |
Proton magnetic moment in Bohr magnetons |
|
0.001521032202 ± 1.5e-11 |
|
78 |
Proton magnetic moment in nuclear magnetons |
|
2.792847386 ± 6.3e-08 |
|
79 |
Diamagnetic shielding correction for protons (H_2 O, spherical sample,
298.15 K) |
(sigma_H2O) |
2.5689e-05 ± 1.5e-08 |
|
80 |
Shielded proton moment (H_2 O, spherical sample, 298.15 K) |
(mu_p') |
1.41057138e-26 ± 4.7e-33 |
J T-1 |
81 |
Shielded proton moment in Bohr magnetons |
|
0.001520993129 ± 1.7e-11 |
|
82 |
Shielded proton moment in nuclear magnetons |
|
2.792775642 ± 6.4e-08 |
|
83 |
Proton gyromagnetic ratio |
(gamma_p) |
267522128 ± 81 |
T-1 s-1 |
84 |
|
(gamma_p) |
42577469 ± 13 |
T-1 s-1 |
85 |
Proton gyromagnetic ratio, uncorrected (H_2 O, spherical sample, 298.15
K) |
(gamma_p') |
267515255 ± 81 |
T-1 s-1 |
86 |
|
(gamma_p'/2pi) |
42576375 ± 13 |
T-1 s-1 |
87 |
Neutron mass |
(m_n) |
1.6749286e-27 ± 1.0e-33 |
kg |
88 |
Neutron mass in u |
|
1.008664904 ± 1.4e-08 |
u |
89 |
Neutron mass in eV |
|
939565630 ± 280 |
eV |
90 |
Neutron-electron mass ratio |
|
1838.683662 ± 4.0e-05 |
|
91 |
Neutron-proton mass ratio |
|
1.001378404 ± 9e-09 |
|
92 |
Neutron molar mass |
|
0.001008664904 ± 1.4e-11 |
kg mol-1 |
93 |
Neutron Compton wavelength |
(lambda_C,n) |
1.3195911e-15 ± 1.2e-22 |
m |
94 |
Neutron magnetic moment |
|
9.6623707e-27 ± 4.0e-33 |
J T-1 |
95 |
Neutron magnetic moment in Bohr magnetons |
|
0.00104187563 ± 2.5e-10 |
|
96 |
Neutron magnetic moment in nuclear magnetons |
|
1.91304275 ± 4.5e-07 |
|
97 |
Neutron-electron magnetic moment ratio |
|
0.00104066882 ± 2.5e-10 |
|
98 |
Neutron-proton magnetic moment ratio |
|
0.68497934 ± 1.6e-07 |
|
99 |
Deuteron mass |
(m_d) |
3.343586e-27 ± 2.0e-33 |
kg |
100 |
Deuteron mass in u |
|
2.013553214 ± 2.4e-08 |
u |
101 |
Deuteron mass in eV |
|
1875613390 ± 570 |
eV |
102 |
Deuteron-electron mass ratio |
|
3670.483014 ± 7.5e-05 |
|
103 |
Deuteron-proton mass ratio |
|
1.999007496 ± 6e-09 |
|
104 |
Deuteron molar mass |
|
0.002013553214 ± 2.4e-11 |
kg mol-1 |
105 |
Deuteron magnetic moment |
(mu_d) |
4.3307375e-27 ± 1.5e-33 |
J T-1 |
106 |
Deuteron magnetic moment in Bohr magnetons |
|
0.0004669754479 ± 9.1e-12 |
|
107 |
Deuteron magnetic moment in nuclear magnetons |
|
0.85743823 ± 2.4e-08 |
|
108 |
Deuteron-electron magnetic moment ratio |
|
0.000466434546 ± 9.1e-12 |
|
109 |
Deuteron-proton magnetic moment ratio |
|
0.3070122035 ± 5.1e-09 |
|
110 |
Avagadro constant |
(N_A) |
6.0221367e+23 ± 3.6e+17 |
mol-1 |
111 |
Atomic mass constant |
(m_u) |
1.6605402e-27 ± 1.0e-33 |
kg |
112 |
Atomic mass constant in eV |
|
931494320 ± 280 |
eV |
113 |
Faraday constant |
(F) |
96485.309 ± 0.029 |
C mol-1 |
114 |
Molar Planck constant |
|
3.99031323e-10 ± 3.6e-17 |
J s mol-1 |
115 |
|
(N_A hc) |
0.11962658 ± 1.1e-07 |
J m mol-1 |
116 |
Molar gas constant |
(R) |
8.31451 ± 7.0e-05 |
J mol-1 K-1 |
117 |
Boltzmann constant |
(k) |
1.380658e-23 ± 1.2e-28 |
J K-1 |
118 |
Boltzmann constant in eV |
|
8.617385e-05 ± 7.3e-10 |
eV K-1 |
119 |
Boltzmann constant in Hz |
|
20836740000 ± 180000 |
K-1 s-1 |
120 |
Boltzmann constant in wavenumbers |
|
69.50387 ± 0.00059 |
m-1 K-1 |
121 |
Molar volume (ideal gas), STP |
(V_m) |
0.0224141 ± 1.9e-07 |
m3 mol-1 |
122 |
Loschmidt constant |
(n_0) |
2.686763e+25 ± 2.3e+20 |
m-3 |
123 |
Stefan-Boltzmann constant |
(sigma) |
5.67051e-08 ± 1.9e-12 |
W m-2 K-4 |
124 |
First radiation constant |
(c_1) |
3.7417749e-16 ± 2.2e-22 |
W m2 |
125 |
Second radiation constant |
(c_2) |
0.01438769 ± 1.2e-07 |
m K |
126 |
Wien displacement law constant |
(b) |
0.002897756 ± 2.4e-08 |
m K |
127 |
Electron volt |
(eV) |
1.60217733e-19 ± 4.9e-26 |
J |
128 |
Atomic mass unit |
(u) |
1.6605402e-27 ± 1.0e-33 |
kg |
129 |
Standard atmosphere |
(atm) |
101325 |
Pa |
130 |
Standard acceleration of gravity |
(g_n) |
9.80665 |
m s-2 |
131 |
BIPM-maintained ohm, Omega_69-B1 as of 1 Jan 85 |
(Omega_B185) |
1-1.563e-6 ± 5.0e-08 |
Omega |
132 |
Drift rate of Omega_69-B1 |
(dOmega_69-B1/dt) |
-0.0566 ± -0.0015 |
muOmega/yr |
133 |
BIPM-maintained volt 483 694 GHz(h/2e) |
(V_76-B1) |
1-7.59e-6 ± 3.0e-07 |
V |
134 |
BIPM maintained ampere A_BIPM |
(A_B185) |
1-6.03e-6 ± 3.0e-07 |
A |
135 |
Cu x-unit: |
(xu(CuKalpha1)) |
1.00207789e-13 ± 7.0e-20 |
m |
136 |
Mo x-unit: |
(xu(MoKalpha1)) |
1.00209938e-13 ± 4.5e-20 |
m |
137 |
AA *: |
(AAngstrom-star) |
1.00001481e-10 ± 9.2e-17 |
m |
138 |
Lattice spacing of Si (in vacuum, 295.65 K) |
(a) |
5.4310196e-10 ± 1.1e-16 |
m |
139 |
Lattice spacing Si (220) plane |
(d_220) |
1.9201554e-10 ± 4.0e-17 |
m |
140 |
Molar volume of Si |
(V_m(Si)) |
1.20588179e-05 ± 8.9e-12 |
m3 mol-1 |