Electron microscopy
Electron Wind Force
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The concept of the ‘electron wind’ driving force was first introduced by Fiks[1] and Huntington and Grone[2]. In the electron wind theory, the number of collisions per unit time between the electrons and a moving atom is given by,
          Nc = neveσe -------------------------- [1155a]
          ne -- the electron density,
          ve-- the average velocity of the electrons,
          σe -- the atom's intrinsic cross section for collision with the electrons.

Then, the the electron wind force can be given by,
          Fw = -|e|neλeσeξ -------------------------- [1155b]
          ξ -- the applied electric field,
          λe -- (= veτe),
         τe -- the relaxation time.

The flux of a solute due to the electron wind force can be given by,
          J = C·m·Zeff·ξ -------------------------- [1155c]
          C -- the concentration of the solute,
          m -- the mobility of the solute,
          Zeff -- the effective charge of the solute.









[1] V. B. Fiks, 1959 Sou. Phys.-Solid State, 1, 14 (1959).
[2] H. B. Huntington and A. R. Crone, J. Phys. Chem. Solids, 20, 76 (1961).