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This is the wiki for Engineering's Solar Cells, Fuel Cells and Batteries.

Useful constants


h - Planck's constant

6.626e-34 J\*s  
4.135e-15 eV\*s

h-bar - Reduced Planck constant, Dirac constant

1.054e-34 J\*s  
6.582e-16 eV\*s

m - Mass of an electron

9.109e-31 kg

e - Charge of a proton, elementary charge

1.602e-19 C

k_B - Boltzmann constant

1.381e-23 J/K  
8.617e-5 eV/K


4.14e-21 J  at 300K  
0.025851 eV  at 300K


ni - Intrinsic carrier concentration

1e10 /cm^3 at 300K

Nv - Valence band density of states

1.83e19 /cm^3

Nc - Conduction band density of states

3.22e19 /cm^3

Eg - Band gap energy Eg

1.12 eV at 300K

m_e - Effective electron mass


m_h - Effective hole mass

Last modified:
Nov. 2, 2013, 2:54 p.m.