Band structure and photoemission studies of SnS2and SnSe2. II. Theoretical

For pt.I see ibid., vol.6, no.24, 3631 (1973). The energy band structures of SnS 2 and SnSe 2 are calculated by a semi-empirical tight-binding method. The band structures are discussed in relation to the optical properties of the materials and to previous calculations which have used the pseudopotential technique. Computation of the valence band density of states and of the energy distribution of the joint density of states for various photon energies is described for the case of SnSe 2 . These results are used to interpret the X-ray and ultraviolet excited photoemission data.