Physical Constants
 Page ID
 9060
Physical Constants  Unit 

Atomic mass unit (u)  1 u = 1.66053906660 × 10^{−24} g 
1 g = 6.0221407621 × 10^{23} u  
Avogadro’s number (N_{A})  6.022142 × 10^{23}/mol 
Boltzmann’s constant (k)  1.380651 × 10^{−23} J/K 
Charge on electron (e)  1.60217634 × 10^{−19} C 
Faraday’s constant (F)  9.6485338 × 10^{4} C/mol 
Gas constant (R)  R=k N_{A} 
0.0820575 (L atm)/(mol K) = 8.31447 J/(mol K) 

Mass of electron (m_{n})  5.485799 × 10^{−4} amu 
= 9.109383 × 10^{−28} g  
Mass of neutron (m_{n})  1.0086649 u 
= 1.6749273 × 10^{−24} g  
Mass of proton (m_{p})  1.0072765 u 
= 1.6726217 × 10^{−24} g  
Pi  π = 3.1415927 
Planck’s constant (h) 
h = 6.626069 × 10 ^{−34}J s \(\hbar=\dfrac{h}{2\pi}\)=1.05457266·10^{34} J·s 
Speed of light in vacuum (c)  c = 2.99792458 × 10^{8} m/s (exact) 

\(\mu_0 = 4\pi\) ·10^{7 }T^{2}·m^{3}/J 12.566370614·10^{7} T^{2}·m^{3}/J 

\(\epsilon_0 = \dfrac{1}{\mu_o\, c^2}\) 8.854187817·10^{12} C^{2}/J·m 

\(\dfrac{1}{137.0359895}\) 

\(\mu_B = \dfrac{e h }{4 \pi \,m_e}\) 9.2740154·10^{24} J/T 

\(\mu_N = \dfrac{e h }{4 \pi \,m_p}\) 5.0507866·10^{27} J/T 

2.002319304386 

\(\gamma_e = \dfrac{2 g_e B}{h}\) 1.7608592·1011 1/s·T \(\dfrac{\gamma_e}{2\pi}\) = 28.024944 GHz/T 

\(\mu_e = \dfrac{ g_e \mu_B}{2}\) 9.2847701·1024 J/T 

2.67515255·10^{8} 1/s·T \(\dfrac{\gamma_p}{2 \pi}\) = 42.576375 MHz/T 

1.41060761·10^{26} J/T 

1.75880·10^{11} C/kg 

5.29177·10^{11} m 

2.81792·10^{15} m 

5.585 

(6.673 ± 0.010)·10^{11} m^{3}/kg·s^{2} (CODATA) 

9.80665 m/s^{2} 

2.42631·10^{12} m 

1 Hartree = \(\dfrac{e^2}{4 \pi \epsilon_o\, a_0}\) 1 Hartree = 2.625501·10^{6} J/mol (approx. 627.5 kcal/mol) 

\(\nu_p = \gamma_p / 2\pi \, B\) \(\nu_p\) = 42.5764 MHz/T (H_{2}O) 

\(\nu_e\) = \(\dfrac{\nu_e}{2\pi}\) (g / ge) B \(\nu_e\) [GHz] = 13.9962 g B [T] g = 0.07144775 \(\nu_e\) [GHz] / B [T] g = 3.04199\(\nu_e\) [GHz] / \(\nu_p\) [MHz] B [T] = 0.0234872 \(\nu_p\) [MHz] 
Conversion of Units 
1 G = 0.1 mT 1 T = 10 kG 1 mT = 10 G A [MHz] = 2.80249 (g / g_{e}) A [G] A [MHz] = 28.0249 (g / g_{e}) A [mT] A [MHz] = 13.9962 g A [mT] A [MHz] = 2.99792·10^{4} A [cm1] A [cm1] = 0.333564·10^{4} A [MHz] A [cm1] = 4.66863·10^{4} g A [mT] 
(Note that the use of brackets [ ] in the following expressions is not in accordance with standards which require the use of a slash, e.g. A/MHz.)