Abstract

Investigations of polytypic crystals have the advantage to allow a comparison of optical transitions in a center, which is situated in different symmetric environments. Cubic ZnS crystals, containing around 10⁻⁸ cm⁻³ nickel atoms, exhibit in the spectral region of about 810 nm several very narrow absorption lines, which can be attributed to crystal field transitions between the ³T₁(F) and the ³T₁(P) term of Ni²⁺ ions.¹⁾ ZnS crystals (with stacking faults), consisting of a great number of polytypic regions, show besides the cubic lines additional structure. Unexpectedly, the linewidth is as narrow as in the crystallographic homogenious case.

© 1984 Optical Society of America