Angstrom unit

10 ^-10 m = 10 ^-8 cm = 10 ^-4 ?m

Avogadro constant

6.02204 10 ²³ mol ^-1

Bohr radius

a ₀

0.52917

Boltzmann constant

k _b

1.38066 10 ^-23 J.K ^-1 (= R/ )

8.61738 10 ^-5 eV.K ^-1

Caloric

cal

4.184 J

Elementary charge

q

1.60218 10 ^-19 C

Electron rest mass

m ₀

0.91095 10 ^-30 kg

Electron Volt

eV

1.60218 10 ^-19 J

23.053 kcal.mol ^-1

Gravitational constant

g

9.81 m.s ^-2

Gas constant

R

1.98719 cal. mol ^-1.K ^-1

8.31440 J.mol ^-1.K ^-1

Permeability in vacuum

? ₀

4 ?10 ^-9 = 1.25633 10 ^-6 H.m ^-1

Permittivity in vacuum

? ₀

8.85418 10 ^-12 F.m ^-1(=1/ ? ₀c ²)

Plank's constant

h

6.62617 10 ^-34 J.s

Reduced Plank's constant

?

1.05458 10 ^-34 J.s(= h/2 ?)

Proton rest mass

M _p

1.67264 10 ^-27 kg

Standard atmosphere

atm

1.01325 10 ⁵ N.m ^-2

Thermal voltage at 300K

k _bT/q

0.0259 V

Velocity of light in vacuum

c

2.99792 10 ⁸ m.s ^-1

Wavelength of 1-eV quantum

?

1.23977 ?m