Semimicroscopic calculation of ion-ion potentials

We derive the imaginary part of the ion-ion potential. We use Feshbach's projection formalism to write an equation for the wave function that describes the relative distance between the centres of mass of the two ions. We assume that the Q-space can be truncated at the excitation of 1p-1h states in either one or the other ion, leaving one of them in its ground state. The projected Schroedinger equation in the chosen subspace contains an effective potential Veff which is truncated at second order of the elementary two-body interactions V. The matrix elements of the elementary interaction are of finite range, represented by an effective Wigner force. The total many-body wave function of the two ions is antisymmetrized only in the partial intrinsic wave function of each ion. This antisymmetrization is not treated explicitly, but contained in the effective interaction. Calculations are done in the Thomas-Fermi approximation. 5 refs., 1 fig. (author)