Materials Data on K6Cd4Sn3Se13 by Materials Project

Abstract

K6Cd4Sn3Se13 crystallizes in the trigonal R3m space group. The structure is three-dimensional. there are two inequivalent K1+ sites. In the first K1+ site, K1+ is bonded in a 4-coordinate geometry to four Se2- atoms. There are two shorter (3.38 Å) and two longer (3.59 Å) K–Se bond lengths. In the second K1+ site, K1+ is bonded in a 4-coordinate geometry to four Se2- atoms. There are two shorter (3.29 Å) and two longer (3.63 Å) K–Se bond lengths. There are two inequivalent Cd2+ sites. In the first Cd2+ site, Cd2+ is bonded to four Se2- atoms to form CdSe4 tetrahedra that share corners with three equivalent CdSe4 tetrahedra and corners with three equivalent SnSe4 tetrahedra. There are one shorter (2.63 Å) and three longer (2.71 Å) Cd–Se bond lengths. In the second Cd2+ site, Cd2+ is bonded to four Se2- atoms to form CdSe4 tetrahedra that share corners with three CdSe4 tetrahedra and corners with three equivalent SnSe4 tetrahedra. There are a spread of Cd–Se bond distances ranging from 2.66–2.71 Å. Sn4+ is bonded to four Se2- atoms to form SnSe4 tetrahedra that share corners with four CdSe4 tetrahedra. There are one shorter (2.55 Å) and three longer (2.58 Å) Sn–Se bond lengths. There are four inequivalent Se2- sites. In the first Se2- site, Se2- is bonded in a 2-coordinate geometry to two K1+, one Cd2+, and one Sn4+ atom. In the second Se2- site, Se2- is bonded to four Cd2+ atoms to form corner-sharing SeCd4 tetrahedra. In the third Se2- site, Se2- is bonded in a 4-coordinate geometry to two equivalent K1+, one Cd2+, and one Sn4+ atom. In the fourth Se2- site, Se2- is bonded to two equivalent K1+, one Cd2+, and one Sn4+ atom to form distorted SeK2CdSn trigonal pyramids that share a cornercorner with one SeCd4 tetrahedra and corners with two equivalent SeK2CdSn trigonal pyramids.