We analyze the low-energy (5-50 eV) electron inelastic mean free path in tr
ansition metals in the framework of a simple density-of-state model. We est
ablish relations between the scattering cross section and the hole numbers.
This allows us to disentangle the different electron-electron scattering c
hannels and, using recently available experimental data, to probe the energ
y dependence of the exchange matrix element. A critical review of the liter
ature leads us to propose numerical mean free path expressions, relevant fo
r several materials.