Peculiarities of chemical bonding in crystals of the in-Se system

Abstract

The investigation of the ab initio band structure and the resulting spatial electron density distribution of the In-Se system in the framework of the density functional theory and the elementary energy bands concept is presented. It gives us reliable information about the valence band structure and peculiarities of the chemical bonding in these crystals. Some regularities in the evolution of the elementary energy bands topology is established, together with the choice of the actual Wyckoff position that is responsible for this topology, at the same time, for the valence band formation in the InSe, In2 Se3, In4 Se3 , and In6 Se7 crystals. The calculated Mulliken charges and the degree of ionicity allow to estimate the character of chemical bonding in these crystals.