see also Units and Conversions
| Symbol | Value | Description |
|---|---|---|
| q | 1.602 × 10-19 coulomb | electronic charge |
| q | 1.602 × 10-19 | conversion from joules to eV |
| m0 | 9.108 × 10-31 kg | electron rest mass |
| c | 2.99792458 × 108 m/s | speed of light in vacuum |
| ε0 | 8.85418 × 10-14 farad/cm 8.85418 × 10-12 farad/m |
permittivity of free space |
| h | 6.62606957 × 10-27 erg·s 6.62606957 × 10-34 joule·s |
Planck's constant |
| k | 1.3806488 × 10-16 erg/K 1.3806488 × 10-23 joule/K |
Boltzmann's constant |
| σ | 5.67 × 10-8 J/m2s K4 | Stefan-Boltzmann constant |
| kT/q | 0.02586 V | thermal voltage at 300 K |
| kT/q | 0.02569 V | thermal voltage at 25°C |
| λ0 | wavelength of 1 eV photon | 1.24 μm |