Energy and angular momentum transfer in the excitation of electron-hole pairs by slow dimers

We calculate the transfer of energy and angular momentum through electron-h ole pair excitations for a slow dimer in an electron gas. We show that the Kohn-Sham procedure can be used under the adiabatic conditions that prevail in the shifted Fermi sphere approximation. We obtain the low-energy limit of the friction coefficient and average angular momentum transfer from a se lf-consistent calculation for the embedded dimer. We apply our theory to H- 2 and LiH molecules. We use our results to evaluate the role of electron-ho le pair excitations when a molecule approaches a metal surface.