Elementary energy bands concept, band structure, and peculiarities of bonding in β-InSe crystal

Abstract

The elementary energy bands concept together with the analysis of the Davydov-like splitting were applied for the first time for investigation of energy band structure and spatial electron density distribution in hexagonal crystals. This approach was used for consideration of the valence band states and for determination of peculiarities of the spatial charge density distribution in the unit cell of the layered β-InSe crystal. It was established that the valence charge density can be located in the so-called Van-der-Waals space. Conclusions following from the elementary energy bands concept were confirmed by the ab initio calculations of the band structure of β-InSe.