Materials Data on Bi2PbSe4 by Materials Project

Abstract

PbBi2Se4 is MAX Phase-like structured and crystallizes in the trigonal R-3m space group. The structure is two-dimensional and consists of three PbBi2Se4 sheets oriented in the (0, 0, 1) direction. Pb2+ is bonded to six equivalent Se2- atoms to form PbSe6 octahedra that share corners with six equivalent BiSe6 octahedra, edges with six equivalent PbSe6 octahedra, and edges with six equivalent BiSe6 octahedra. The corner-sharing octahedral tilt angles are 1°. All Pb–Se bond lengths are 3.08 Å. Bi3+ is bonded to six Se2- atoms to form BiSe6 octahedra that share corners with three equivalent PbSe6 octahedra, edges with three equivalent PbSe6 octahedra, and edges with six equivalent BiSe6 octahedra. The corner-sharing octahedral tilt angles are 1°. There are three shorter (2.89 Å) and three longer (3.12 Å) Bi–Se bond lengths. There are two inequivalent Se2- sites. In the first Se2- site, Se2- is bonded in a 3-coordinate geometry to three equivalent Bi3+ atoms. In the second Se2- site, Se2- is bonded to three equivalent Pb2+ and three equivalent Bi3+ atoms to form a mixture of edge and corner-sharing SeBi3Pb3 octahedra. The corner-sharing octahedral tilt angles are 0°.