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Individual stopping powers:

A more rigorous treatment of inelastic scattering processes and the electron energy loss is the summation of individual theoretical stopping powers. The simplest possibility is to distinguish between innershell excitation and valence electron excitation. The total energy loss due to valence electron excitation is calculated by:

 

where the stopping power for valence electron excitation is estimated by the difference of the Bethe stopping power and the stopping power for inner-shell electron ionization:

 

The formula of the Bethe stopping power is formula A.4 and formula A.5 for small electron energies ().

The inner shell stopping power was published by Gryzinski:

The angular deflections caused by inelastic scattering events are related to the energy loss according to a classical approach [Sch86] (momentum and energy conservation):

 

A rigorous summation of all stopping power during an inelastic scattering process has been proposed by Ritchie [RGNB69]. A modified approach is by Shimizu and includes:

  1. Electron--conduction electron scattering [Str59]
  2. Electron--plasmon scattering [Qui62]
  3. Electron--shell electron scattering [Gry65]

Further information can be found in the review paper of Shimizu [SD92].



Horst Wagner
Tue Mar 19 10:24:55 MET 1996