Materials Data on Fe2NiSe4 by Materials Project

Abstract

Fe2NiSe4 crystallizes in the triclinic P1 space group. The structure is three-dimensional. 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 five equivalent NiSe5 trigonal bipyramids, edges with two equivalent FeSe6 octahedra, and an edgeedge with one NiSe5 trigonal bipyramid. There are a spread of Fe–Se bond distances ranging from 2.38–2.44 Å. In the second Fe3+ site, Fe3+ is bonded in a 5-coordinate geometry to five Se2- atoms. There are a spread of Fe–Se bond distances ranging from 2.33–2.44 Å. Ni2+ is bonded to five Se2- atoms to form distorted NiSe5 trigonal bipyramids that share corners with five equivalent FeSe6 octahedra, corners with two equivalent NiSe5 trigonal bipyramids, and an edgeedge with one FeSe6 octahedra. The corner-sharing octahedra tilt angles range from 52–61°. There are a spread of Ni–Se bond distances ranging from 2.34–2.42 Å. There are four inequivalent Se2- sites. In the first Se2- site, Se2- is bonded in a 4-coordinate geometry to three Fe3+ and one Ni2+ atom. In the second Se2- site, Se2- is bonded in a 4-coordinate geometry to three Fe3+ and one Ni2+ atom. In the third Se2- site, Se2- is bonded in a 4-coordinate geometry to two Fe3+ and two equivalent Ni2+ atoms. In the fourth Se2- site, Se2- is bonded in a 4-coordinate geometry to three Fe3+ and one Ni2+ atom.