Materials Data on Cd2Bi2(TeSe)3 by Materials Project

Abstract

Cd2Bi2(TeSe)3 is Caswellsilverite-derived structured and crystallizes in the trigonal R3m space group. The structure is three-dimensional. there are two inequivalent Cd2+ sites. In the first Cd2+ site, Cd2+ is bonded to three equivalent Te2- and three equivalent Se2- atoms to form CdTe3Se3 octahedra that share corners with three equivalent BiSe6 octahedra, edges with three equivalent BiSe6 octahedra, and edges with six equivalent CdTe3Se3 octahedra. The corner-sharing octahedral tilt angles are 4°. All Cd–Te bond lengths are 2.96 Å. All Cd–Se bond lengths are 2.96 Å. In the second Cd2+ site, Cd2+ is bonded to three equivalent Te2- and three equivalent Se2- atoms to form CdTe3Se3 octahedra that share corners with three equivalent BiTe3Se3 octahedra, corners with three equivalent SeBi3Te3 octahedra, edges with three equivalent BiTe3Se3 octahedra, edges with three equivalent SeBi3Te3 octahedra, and edges with six equivalent CdTe3Se3 octahedra. The corner-sharing octahedra tilt angles range from 2–15°. All Cd–Te bond lengths are 2.91 Å. All Cd–Se bond lengths are 3.01 Å. There are two inequivalent Bi4+ sites. In the first Bi4+ site, Bi4+ is bonded to three equivalent Te2- and three equivalent Se2- atoms to form BiTe3Se3 octahedra that share corners with three equivalent CdTe3Se3 octahedra, edges with three equivalent CdTe3Se3 octahedra, and edges with six equivalent BiTe3Se3 octahedra. The corner-sharing octahedral tilt angles are 2°. All Bi–Te bond lengths are 3.09 Å. All Bi–Se bond lengths are 3.08 Å. In the second Bi4+ site, Bi4+ is bonded to six Se2- atoms to form BiSe6 octahedra that share corners with three equivalent CdTe3Se3 octahedra, corners with three equivalent TeCd3Se3 octahedra, edges with three equivalent CdTe3Se3 octahedra, edges with three equivalent TeCd3Se3 octahedra, and edges with six equivalent BiSe6 octahedra. The corner-sharing octahedra tilt angles range from 4–14°. There are three shorter (2.91 Å) and three longer (3.12 Å) Bi–Se bond lengths. There are three inequivalent Te2- sites. In the first Te2- site, Te2- is bonded in a 6-coordinate geometry to three equivalent Cd2+ and three equivalent Te2- atoms. All Te–Te bond lengths are 3.46 Å. In the second Te2- site, Te2- is bonded to three equivalent Cd2+ and three equivalent Se2- atoms to form distorted TeCd3Se3 octahedra that share corners with three equivalent BiSe6 octahedra, corners with three equivalent SeCd3Bi3 octahedra, edges with three equivalent BiSe6 octahedra, edges with three equivalent SeCd3Bi3 octahedra, and edges with six equivalent TeCd3Se3 octahedra. The corner-sharing octahedra tilt angles range from 3–14°. All Te–Se bond lengths are 3.60 Å. In the third Te2- site, Te2- is bonded in a 6-coordinate geometry to three equivalent Bi4+ and three equivalent Te2- atoms. There are three inequivalent Se2- sites. In the first Se2- site, Se2- is bonded to three equivalent Bi4+ and three equivalent Te2- atoms to form distorted SeBi3Te3 octahedra that share corners with three equivalent CdTe3Se3 octahedra, corners with three equivalent SeCd3Bi3 octahedra, edges with three equivalent CdTe3Se3 octahedra, and edges with nine SeBi3Te3 octahedra. The corner-sharing octahedra tilt angles range from 5–15°. In the second Se2- site, Se2- is bonded to three equivalent Cd2+ and three equivalent Bi4+ atoms to form a mixture of corner and edge-sharing SeCd3Bi3 octahedra. The corner-sharing octahedral tilt angles are 5°. In the third Se2- site, Se2- is bonded to three equivalent Cd2+ and three equivalent Bi4+ atoms to form SeCd3Bi3 octahedra that share corners with three equivalent TeCd3Se3 octahedra, edges with three equivalent TeCd3Se3 octahedra, and edges with six equivalent SeCd3Bi3 octahedra. The corner-sharing octahedral tilt angles are 3°.