Electronic Structure and X-Ray Photoelectron Spectra of Some Perovskite Molecular Crystals

Abstract

It is new study of some molecular crystals with a perovskite structure, whose luminescent, thermochromic, nonlinear optical and dielectric properties provide opportunities for their wide practical application. This paper presents the results of an investigation of the electronic structure and the orbital nature of crystals with the AMX6 formula (where A = Cs, HGu; M = Te, Sb, Ir, Os, Re, W; X = F, Cl, Br). The electronic structure of crystals with Te and Sb atoms was determined by the method of X-ray photoelectron spectroscopy and quantum-chemical modeling within the framework of the density functional theory. We identified the molecular orbitals which are responsible for covalent metal-halogen binding. Also we found that the transition from the 3a1g highest occupied molecular orbital to the 4t1u lowest unoccupied molecular orbital, which corresponds to the states 1T1u and 3T1u, is responsible for the luminescence of the [MX6] 2– anions.