Materials Data on V4As3 by Materials Project

Abstract

V4As3 crystallizes in the orthorhombic Cmcm space group. The structure is three-dimensional. there are five inequivalent V+2.25+ sites. In the first V+2.25+ site, V+2.25+ is bonded in a square co-planar geometry to four As3- atoms. There are two shorter (2.51 Å) and two longer (2.58 Å) V–As bond lengths. In the second V+2.25+ site, V+2.25+ is bonded to six As3- atoms to form VAs6 octahedra that share corners with eight equivalent VAs6 octahedra, corners with four equivalent VAs5 trigonal bipyramids, edges with two equivalent VAs6 octahedra, edges with four equivalent VAs5 square pyramids, and faces with two equivalent VAs6 octahedra. The corner-sharing octahedra tilt angles range from 42–53°. There are a spread of V–As bond distances ranging from 2.45–2.56 Å. In the third V+2.25+ site, V+2.25+ is bonded to six As3- atoms to form VAs6 octahedra that share corners with six VAs6 octahedra, corners with five equivalent VAs5 square pyramids, corners with two equivalent VAs5 trigonal bipyramids, edges with two equivalent VAs6 octahedra, edges with three equivalent VAs5 trigonal bipyramids, faces with two VAs6 octahedra, and a faceface with one VAs5 square pyramid. The corner-sharing octahedra tilt angles range from 42–53°. There are a spread of V–As bond distances ranging from 2.45–2.60 Å. In the fourth V+2.25+ site, V+2.25+ is bonded to five As3- atoms to form VAs5 square pyramids that share corners with five equivalent VAs6 octahedra, a cornercorner with one VAs5 square pyramid, corners with six equivalent VAs5 trigonal bipyramids, edges with two equivalent VAs6 octahedra, edges with two equivalent VAs5 square pyramids, edges with two equivalent VAs5 trigonal bipyramids, and a faceface with one VAs6 octahedra. The corner-sharing octahedra tilt angles range from 38–57°. There are three shorter (2.49 Å) and two longer (2.52 Å) V–As bond lengths. In the fifth V+2.25+ site, V+2.25+ is bonded to five As3- atoms to form VAs5 trigonal bipyramids that share corners with four VAs6 octahedra, corners with six equivalent VAs5 square pyramids, edges with three equivalent VAs6 octahedra, edges with two equivalent VAs5 square pyramids, and edges with four equivalent VAs5 trigonal bipyramids. The corner-sharing octahedra tilt angles range from 25–45°. There are a spread of V–As bond distances ranging from 2.51–2.56 Å. There are four inequivalent As3- sites. In the first As3- site, As3- is bonded to six V+2.25+ atoms to form a mixture of distorted edge and corner-sharing AsV6 pentagonal pyramids. In the second As3- site, As3- is bonded to six V+2.25+ atoms to form a mixture of distorted edge, corner, and face-sharing AsV6 pentagonal pyramids. In the third As3- site, As3- is bonded in a 7-coordinate geometry to seven V+2.25+ atoms. In the fourth As3- site, As3- is bonded in a 8-coordinate geometry to eight V+2.25+ atoms.