Materials Data on CdHg4Se5 by Materials Project

Abstract

Hg4CdSe5 is Caswellsilverite-like structured and crystallizes in the trigonal R-3m space group. The structure is three-dimensional. there are two inequivalent Hg2+ sites. In the first Hg2+ site, Hg2+ is bonded to six Se2- atoms to form HgSe6 octahedra that share corners with three equivalent HgSe6 octahedra, corners with three equivalent CdSe6 octahedra, edges with three equivalent CdSe6 octahedra, and edges with nine HgSe6 octahedra. The corner-sharing octahedra tilt angles range from 0–1°. There are three shorter (2.90 Å) and three longer (2.93 Å) Hg–Se bond lengths. In the second Hg2+ site, Hg2+ is bonded to six Se2- atoms to form a mixture of corner and edge-sharing HgSe6 octahedra. The corner-sharing octahedral tilt angles are 0°. There are three shorter (2.90 Å) and three longer (2.91 Å) Hg–Se bond lengths. Cd2+ is bonded to six equivalent Se2- atoms to form CdSe6 octahedra that share corners with six equivalent HgSe6 octahedra, edges with six equivalent HgSe6 octahedra, and edges with six equivalent CdSe6 octahedra. The corner-sharing octahedral tilt angles are 1°. All Cd–Se bond lengths are 2.88 Å. There are three inequivalent Se2- sites. In the first Se2- site, Se2- is bonded to three equivalent Hg2+ and three equivalent Cd2+ atoms to form a mixture of corner and edge-sharing SeCd3Hg3 octahedra. The corner-sharing octahedra tilt angles range from 0–1°. In the second Se2- site, Se2- is bonded to six equivalent Hg2+ atoms to form a mixture of corner and edge-sharing SeHg6 octahedra. The corner-sharing octahedral tilt angles are 0°. In the third Se2- site, Se2- is bonded to six Hg2+ atoms to form a mixture of corner and edge-sharing SeHg6 octahedra. The corner-sharing octahedra tilt angles range from 0–1°.