Anomalous Variation of Band Gap with Composition in Zinc Sulfo- and Seleno-Tellurides

A monotonic variation of band gap with composition occurs for many binary solid solutions. Of some Group II-Group VI systems, ZnS-ZnSe shows this type of variation of band gap with composition, whereas ZnSe-ZnTe, ZnS-ZnTe show an anomalous minimum in a plot of band gap versus composition of the solid solution.