Similarities of the band structure of In₄Se₃ and InSe under pressure and peculiarities of the creation of the band gap

Abstract

Abstract The existence of the physical elementary energy bands describing the Davydov splitting was demonstrated in the energy spectra of the layered orthorhombic In 4 Se 3 crystal. It was confirmed that the physical elementary energy bands are related to the exactly determined Wyckoff position in the unit cell, where the maximum of the valence electron density is localized. By means of ab initio calculations, the dispersion laws with the low‐energy non‐parabolicity were obtained for electrons and holes of the In 4 Se 3 crystal. The reasons for such a dispersion law to occur in In 4 Se 3 are discussed as well as its similarity to the dispersion law for holes in the β ‐InSe crystal under pressure. (© 2006 WILEY‐VCH Verlag GmbH & Co. KGaA, Weinheim)