Physical Constants

Atomic mass unit (amu)	1 amu = 1.6605389 × 10−24 g
	1 g = 6.022142 × 1023 amu
Avogadro’s number (NA)	6.022142 × 1023/mol
Boltzmann’s constant (k)	1.380651 × 10−23 J/K
Charge on electron (e)	1.6021765 × 10−19 C
Faraday’s constant (F)	9.6485338 × 104 C/mol
Gas constant (R)	R=k NA
	0.0820575 (L atm)/(mol K) = 8.31447 J/(mol K)
Mass of electron (mn)	5.485799 × 10−4 amu
	= 9.109383 × 10−28 g
Mass of neutron (mn)	1.0086649 amu
	= 1.6749273 × 10−24 g
Mass of proton (mp)	1.0072765 amu
	= 1.6726217 × 10−24 g
Pi	π = 3.1415927
Planck’s constant (h)	h = 6.626069 × 10 −34J s ℏ=h2π=1.05457266·10-34 J·s
Speed of light in vacuum (c)	c = 2.99792458 × 108 m/s (exact)
Permeability of vacuum μ0	μ0=4π ·10-7 T2·m3/J 12.566370614·10-7 T2·m3/J
Permittivity of vacuum ϵ0	ϵ0=1μoc2 8.854187817·10-12 C2/J·m
Fine structure constant α	1137.0359895
Bohr magneton μB	μB=eh4πme 9.2740154·10-24 J/T
Nuclear magneton μN	μN=eh4πmp 5.0507866·10-27 J/T
Free electron g factor ge	2.002319304386
Free electron gyromagnetic ratio γe	γe=2geBh 1.7608592·1011 1/s·T γe2π = 28.024944 GHz/T
Electron magnetic moment μe	μe=−geμB2 -9.2847701·10-24 J/T
Proton gyromagnetic ratio (H2O) γp	2.67515255·108 1/s·T γp2π = 42.576375 MHz/T
Proton magnetic momentμp	1.41060761·10-26 J/T
Charge-to-mass ratio for the electron eme	1.75880·1011 C/kg
Bohr radius a0	5.29177·10-11 m
Electron radius re	2.81792·10-15 m
Proton g factor (Landé factor) gH	5.585
Gravitational constant G	(6.673 ± 0.010)·10-11 m3/kg·s2 (CODATA)
Acceleration due to gravity g	9.80665 m/s2
Compton wavelength of the electron λc	2.42631·10-12 m
Atomic energy unit Hartree	1 Hartree = e24πϵoa0 1 Hartree = 2.625501·106 J/mol (approx. 627.5 kcal/mol)
Proton Larmor frequency	νp=γp/2πB νp = 42.5764 MHz/T (H2O)
Electron Larmor frequency	νe = νe2π (g / ge) B νe [GHz] = 13.9962 g B [T] g = 0.07144775 νe [GHz] / B [T] g = 3.04199νe [GHz] / νp [MHz] B [T] = 0.0234872 νp [MHz]
Conversion of Units	1 G = 0.1 mT 1 T = 10 kG 1 mT = 10 G A [MHz] = 2.80249 (g / ge) A [G] A [MHz] = 28.0249 (g / ge) A [mT] A [MHz] = 13.9962 g A [mT] A [MHz] = 2.99792·104 A [cm-1] A [cm-1] = 0.333564·10-4 A [MHz] A [cm-1] = 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.)