The crystal structures of semiconductors and a general valence rule

Compound semiconductors are valence compounds, the great majority of which contain anions lying to the right of the Zintl border (atoms of Groups IV- VII excluding transition metals). These therefore satisfy a general valence rule and this provides a systematic means of discussing their crystal chemistry based on anion substructural arrays. The discussion embraces polyanionic, polycationic and normal valence compounds. Essential features of structures of polyanionic compounds were first pointed out by Busmann.