Kristallstruktur und Doppelbrechung fehlgeordneter ZnS Einkristalle

By comparing the crystal structure (investigated by means of X-ray diffraction) and the birefringence of disordered ZnS crystals it is shown that the birefringence Δn is proportional to the hexagonality σ, i.e. Δn = σ ^. Δn_Wurt. The hexagonality σ is the part of hexagonal packing elements, Δn_Wurt the birefringence of Wurtzite.