Electronic structure of amorphous germanium sulphides

• Published in: Journal of non-crystalline solids Vol. 312; pp. 566 - 569
• Main Author: Hachiya, Kan
• Format: Journal Article Conference Proceeding
• Language: English
• Published: Amsterdam Elsevier B.V 01.10.2002; Elsevier
• Subjects: Amorphous semiconductors, metallic glasses, glasses; Condensed matter: electronic structure, electrical, magnetic, and optical properties; Electron states; Electronic structure of disordered solids; Electronic structure of liquid metals and semiconductors and their alloys; Exact sciences and technology; Physics; E250; A095; 71.23.Cq; A200; 71.23.−k; Photoelectron spectra; Liquid state; Valence bands; Electronic structure; Inorganic compounds; Molecular orbital method; Binary compounds; Amorphous state; Germanium sulfides; Electronic density of states; Experimental study; Cluster model
• ISSN: 0022-3093; 1873-4812
• DOI: 10.1016/S0022-3093(02)01781-7

First-principles calculations results are presented for the electronic structures of amorphous and liquid Ge–S. Model cluster calculation of the density of states using a geometry similar to that of the crystalline state coordination in GeS 2 can reproduce the peak structure of the experimental valence band (VB) photoemission spectra. Conduction band densities of states are also calculated and their structure is interpreted together with the VB. The present calculations confirm that the states at the VB top are lone-pair states, and that the VB below them and the conduction band are bonding or anti-bonding states of the Ge–S bond. A definite shape of the molecular orbitals around the bandgap is also revealed.