Exchange interaction between orbitally degenerate ions Case of two2Pions

Abstract

The problem of the exchange interaction between two 2 P ions is studied. As a first step, from the true electrostatic hamiltonian, the symmetry and the energy of each term arising from the interaction between two orbitally degenerate ions are determined. As a second step, a phenomenological model, invariant with respect to a unitary transformation between the atomic orbital basis functions leading to the same terms as the true electrostatic perturbation, is proposed.