Alkali-Metal Substitution into Solid-State Chalcogenides: Effects on Dimensionality

The structures of many binary solid-state chalcogenides (chalcogen = S, Se, Te) are known along with the structures of the related ternaries formed by addition of an alkali metal. Similarly, the structures of many ternary solid-state chalcogenides are known along with the structures of the related quaternaries formed by addition of an alkali metal. The dimensionality of such compounds has been examined through a review of the literature. It is found in general that addition of the alkali metal lowers the dimensionality of the resultant structure. This trend, which appears to be general, is illustrated and discussed.