Materials Data on FeCu2SnSe4 by Materials Project

Abstract

Cu2FeSnSe4 crystallizes in the trigonal R3m space group. The structure is three-dimensional. Fe3+ is bonded to four Se2- atoms to form FeSe4 tetrahedra that share corners with three equivalent CuSe4 tetrahedra and corners with six equivalent FeSe4 tetrahedra. There are one shorter (2.31 Å) and three longer (2.41 Å) Fe–Se bond lengths. There are two inequivalent Cu+1.50+ sites. In the first Cu+1.50+ site, Cu+1.50+ is bonded to four Se2- atoms to form CuSe4 tetrahedra that share corners with three equivalent FeSe4 tetrahedra and corners with nine CuSe4 tetrahedra. There are one shorter (2.39 Å) and three longer (2.41 Å) Cu–Se bond lengths. In the second Cu+1.50+ site, Cu+1.50+ is bonded to four Se2- atoms to form corner-sharing CuSe4 tetrahedra. There are three shorter (2.37 Å) and one longer (2.50 Å) Cu–Se bond lengths. Sn2+ is bonded in a 4-coordinate geometry to four Se2- atoms. There are three shorter (2.78 Å) and one longer (3.37 Å) Sn–Se bond lengths. There are four inequivalent Se2- sites. In the first Se2- site, Se2- is bonded to four Cu+1.50+ atoms to form corner-sharing SeCu4 tetrahedra. In the second Se2- site, Se2- is bonded in a distorted rectangular see-saw-like geometry to one Cu+1.50+ and three equivalent Sn2+ atoms. In the third Se2- site, Se2- is bonded in a distorted trigonal non-coplanar geometry to three equivalent Fe3+ and one Sn2+ atom. In the fourth Se2- site, Se2- is bonded to one Fe3+ and three equivalent Cu+1.50+ atoms to form corner-sharing SeFeCu3 tetrahedra.