Materials Data on V(FeSe2)2 by Materials Project

Abstract

V(FeSe2)2 crystallizes in the monoclinic Cm space group. The structure is three-dimensional. V2+ is bonded to six Se2- atoms to form distorted VSe6 octahedra that share corners with six equivalent FeSe6 octahedra, edges with two equivalent VSe6 octahedra, edges with four equivalent FeSe6 octahedra, and a faceface with one FeSe6 octahedra. The corner-sharing octahedra tilt angles range from 52–57°. There are a spread of V–Se bond distances ranging from 2.39–2.75 Å. There are two inequivalent Fe3+ sites. In the first Fe3+ site, Fe3+ is bonded to six Se2- atoms to form FeSe6 octahedra that share corners with six equivalent VSe6 octahedra, corners with six equivalent FeSe6 octahedra, edges with two equivalent FeSe6 octahedra, a faceface with one VSe6 octahedra, and a faceface with one FeSe6 octahedra. The corner-sharing octahedra tilt angles range from 51–57°. There are a spread of Fe–Se bond distances ranging from 2.43–2.53 Å. In the second Fe3+ site, Fe3+ is bonded to six Se2- atoms to form distorted FeSe6 octahedra that share corners with six equivalent FeSe6 octahedra, edges with two equivalent FeSe6 octahedra, edges with four equivalent VSe6 octahedra, and a faceface with one FeSe6 octahedra. The corner-sharing octahedra tilt angles range from 51–56°. There are a spread of Fe–Se bond distances ranging from 2.38–2.70 Å. There are four inequivalent Se2- sites. In the first Se2- site, Se2- is bonded in a 5-coordinate geometry to one V2+ and four Fe3+ atoms. In the second Se2- site, Se2- is bonded in a 5-coordinate geometry to two equivalent V2+ and three Fe3+ atoms. In the third Se2- site, Se2- is bonded in a 4-coordinate geometry to two equivalent V2+ and two Fe3+ atoms. In the fourth Se2- site, Se2- is bonded in a 4-coordinate geometry to one V2+ and three Fe3+ atoms.