Materials Data on K4Sn3Se8 by Materials Project

Abstract

K4Sn3Se8 crystallizes in the orthorhombic Ccce space group. The structure is three-dimensional. there are two inequivalent K1+ sites. In the first K1+ site, K1+ is bonded in a 8-coordinate geometry to eight Se2- atoms. There are a spread of K–Se bond distances ranging from 3.37–3.68 Å. In the second K1+ site, K1+ is bonded in a 6-coordinate geometry to six equivalent Se2- atoms. There are a spread of K–Se bond distances ranging from 3.42–3.54 Å. There are two inequivalent Sn4+ sites. In the first Sn4+ site, Sn4+ is bonded to four Se2- atoms to form edge-sharing SnSe4 tetrahedra. There are two shorter (2.52 Å) and two longer (2.67 Å) Sn–Se bond lengths. In the second Sn4+ site, Sn4+ is bonded to four equivalent Se2- atoms to form edge-sharing SnSe4 tetrahedra. All Sn–Se bond lengths are 2.59 Å. There are two inequivalent Se2- sites. In the first Se2- site, Se2- is bonded in a 1-coordinate geometry to five K1+ and one Sn4+ atom. In the second Se2- site, Se2- is bonded to two equivalent K1+ and two Sn4+ atoms to form a mixture of corner and edge-sharing SeK2Sn2 trigonal pyramids.