The NIST Reference on Constants, Units and Uncertainty

Fundamental Physical Constants
Constants
Topics:
Values
Energy
Equivalents
Searchable
Bibliography
Background
Constants
Bibliography
Constants,
Units &
Uncertainty
home page
Basis of conversion factors for energy equivalents

Conversion factors for energy equivalents are derived from the following relations:

    E = mc2 = hc/ = hnu = kT 

    1 eV = (e/C) J

    1 u = mu = (1/12) m (12C) = 2Rh/(Ar(e) 2c)

    Eh = 2Rhc = 2mec2.