Materials Data on Fe3NiAs4 by Materials Project

Fe3NiAs4 is Modderite-derived structured and crystallizes in the monoclinic Pm space group. The structure is three-dimensional. there are three inequivalent Fe3+ sites. In the first Fe3+ site, Fe3+ is bonded to six As3- atoms to form distorted FeAs6 octahedra that share corners with four equivalent NiAs6 octahedra, corners with eight equivalent FeAs6 octahedra, edges with six FeAs6 octahedra, and faces with two equivalent NiAs6 octahedra. The corner-sharing octahedra tilt angles range from 47–58°. There are a spread of Fe–As bond distances ranging from 2.32–2.52 Å. In the second Fe3+ site, Fe3+ is bonded to six As3- atoms to form FeAs6 octahedra that share corners with twelve FeAs6 octahedra, edges with two equivalent FeAs6 octahedra, edges with four equivalent NiAs6 octahedra, and faces with two equivalent FeAs6 octahedra. The corner-sharing octahedra tilt angles range from 46–58°. There are a spread of Fe–As bond distances ranging from 2.36–2.45 Å. In the third Fe3+ site, Fe3+ is bonded to six As3- atoms to form distorted FeAs6 octahedra that share corners with four equivalent FeAs6 octahedra, corners with eight equivalent NiAs6 octahedra, edges with six FeAs6 octahedra, and faces with two equivalent FeAs6 octahedra. The corner-sharing octahedra tilt angles range from 45–59°. There are a spread of Fe–As bond distances ranging from 2.27–2.46 Å. Ni3+ is bonded to six As3- atoms to form distorted NiAs6 octahedra that share corners with twelve FeAs6 octahedra, edges with two equivalent NiAs6 octahedra, edges with four equivalent FeAs6 octahedra, and faces with two equivalent FeAs6 octahedra. The corner-sharing octahedra tilt angles range from 45–59°. There are a spread of Ni–As bond distances ranging from 2.34–2.55 Å. There are four inequivalent As3- sites. In the first As3- site, As3- is bonded in a 6-coordinate geometry to five Fe3+ and one Ni3+ atom. In the second As3- site, As3- is bonded in a 6-coordinate geometry to five Fe3+ and one Ni3+ atom. In the third As3- site, As3- is bonded in a 6-coordinate geometry to four Fe3+ and two equivalent Ni3+ atoms. In the fourth As3- site, As3- is bonded in a 6-coordinate geometry to four Fe3+ and two equivalent Ni3+ atoms.