Materials Data on Nb2V4Si5 by Materials Project
Nb2V4Si5 crystallizes in the orthorhombic Ibam space group. The structure is three-dimensional. Nb2+ is bonded to six Si+2.40- atoms to form distorted NbSi6 octahedra that share corners with four equivalent NbSi6 octahedra, corners with six equivalent VSi7 pentagonal bipyramids, edges with two equivalent NbSi6 octahedra, faces with two equivalent NbSi6 octahedra, and faces with four equivalent VSi7 pentagonal bipyramids. The corner-sharing octahedral tilt angles are 36°. There are a spread of Nb–Si bond distances ranging from 2.57–2.66 Å. There are two inequivalent V2+ sites. In the first V2+ site, V2+ is bonded to seven Si+2.40- atoms to form VSi7 pentagonal bipyramids that share corners with six equivalent NbSi6 octahedra, corners with six equivalent VSi7 pentagonal bipyramids, edges with three equivalent VSi7 pentagonal bipyramids, faces with four equivalent NbSi6 octahedra, and faces with two equivalent VSi7 pentagonal bipyramids. The corner-sharing octahedra tilt angles range from 42–55°. There are a spread of V–Si bond distances ranging from 2.58–2.86 Å. In the second V2+ site, V2+ is bonded in a 7-coordinate geometry to seven Si+2.40- atoms. There are a spread of V–Si bond distances ranging from 2.35–2.83 Å. There are three inequivalent Si+2.40- sites. In the first Si+2.40- site, Si+2.40- is bonded in a 8-coordinate geometry to two equivalent Nb2+, five V2+, and one Si+2.40- atom. The Si–Si bond length is 2.42 Å. In the second Si+2.40- site, Si+2.40- is bonded in a 9-coordinate geometry to four equivalent Nb2+ and five V2+ atoms. In the third Si+2.40- site, Si+2.40- is bonded in a 10-coordinate geometry to eight V2+ and two equivalent Si+2.40- atoms. Both Si–Si bond lengths are 2.57 Å.