Practical Electron Microscopy and Database

The Bethe stopping power (or Bethe equation) was modified by Joy and Luo [1] and is given by,

               ----------------------------- [4422]

where, E -- Energy of the electron (in eV)
           Z -- Atomic number
           A -- Atomic weight
           ρ -- Density of the material (in g/cm³)
           K -- Modification coefficient, which depends on target materials and can be obtained by the relation K = 0.734 Z^0.037 [2]
           J -- Mean ionization potential (in eV)

[1] D. C. Joy, S. Luo, Scanning 11 (1989) 176.
[2] R. Gauvin, G. L'Espérance, S. St-Laurent, Scanning 14 (1992) 37.