A new representative of the cubic parkerites family: Synthesis, crystal and electronic structure of Pt3Bi2Se2

Abstract

A new mixed platinum-bismuth selenide, Pt3Bi2Se2, was synthesized by a high-temperature ampoule technique. Its crystal structure was determined by Rietveld method from X-ray powder diffraction data. Pt3Bi2Se2 crystallizes in the cubic system with I213 space group: a = 8.49336(5) Å, Z = 4, Rp = 0.037, Rb = 0.014. The compound represents a rare example of the cubic parkerite structure and is isotypic with Pd3Bi2S2. Its electronic structure was evaluated from quantum chemical calculations on the density functional theory level. Pt3Bi2Se2 is found to exhibit metallic properties and Pauli-like paramagnetic behavior. Chemical bonding was evaluated using the combination of Bader's QTAIM approach and the topological analysis of electron localizability indicator. According to that data, three dimensional framework of Pt3Bi2Se2 is largely based on covalent Pt–Se and polar covalent Pt–Bi pairwise interactions.