The Mean Free Paths of Very Low Energy Electrons: the Effects of Exchange and Correlation
David R. Penn
The mean free paths of low-energy electrons in a free-electron-like material are calculated using a screened electron-electron interaction which is antisymmetrized for the case of parallel-spin electrons. Calculations are carried out for several different approximations of the screenign function: Fermi-Thomas, Lindhard, Singwi, and Kukkonen-Overhauser. The first three yield mean free paths that agree to within 10%, while the Kukkonen-Overhauser screening yields mean free paths that are roughly half those given by the other aproximations. The effect of the Pauli principal in all cases is that the scattering between antiparallel-spin electrons is roughly three to ten times stronger than between parallel-spin electrons.
Physical Review B (Condensed Matter and Materials Physics)