Binding energy of wannier excitons interacting with LO phonons in anisotropic polar crystals

The binding energy of an exciton is calculated taking into account its interaction with optical phonons as well as the anisotropy of the band masses and the dielectric constants. For not too large anisotropies one might approximate the exciton–phonon interaction by an isotropic effective potential with averaged material constants. In II–VI compounds the energies calculated with this isotropic potential agree quite well with the experimental results.