Investigation of electronic properties of crystalline arsenic chalcogenides: Theory and experiment

✍ Scribed by Pankaj Srivastava; Hosiyar Singh Mund; Yamini Sharma

• Publisher: Elsevier Science
• Year: 2011
• Tongue: English
• Weight: 591 KB
• Volume: 406
• Category: Article
• ISSN: 0921-4526
• DOI: 10.1016/j.physb.2011.05.012

✦ Synopsis

The electronic structure of crystalline As 2 S 3 and As 2 Se 3 has been calculated in this paper. We present the energy bands, density of states (DOS) and the Compton profiles using the linear combination of atomic orbitals (LCAO) scheme based on the density functional theory (DFT). From the calculated total and partial density of states it is seen that the lone-pair p-states of sulphur/selenium contribute closest to the Fermi energy level. To interpret the theoretical data on the Compton line shape, we have measured the Compton profiles on a 100 mCi 241 Am spectrometer. It is seen that the density functional theory within generalised gradient approximation gives a slightly better agreement with the experimental momentum densities. The nature of chemical bonding in arsenic chalcogenides is studied using Mulliken's population analysis and the experimentally measured equal-valence-electron-density profiles; As 2 S 3 is found to be more ionic compared to As 2 Se 3 .