DOI: 10.17188/1692820
title: Materials Data on Nb5Si6Mo5 by Materials Project

description: Nb5Mo5Si6 crystallizes in the monoclinic Cm space group. The structure is three-dimensional. there are four inequivalent Nb+2.60+ sites. In the first Nb+2.60+ site, Nb+2.60+ is bonded to six Si4- atoms to form distorted NbSi6 pentagonal pyramids that share corners with six NbSi6 pentagonal pyramids, corners with nine MoSi6 pentagonal pyramids, corners with four equivalent NbSi4 tetrahedra, edges with three equivalent MoSi6 pentagonal pyramids, edges with two equivalent NbSi4 tetrahedra, faces with two equivalent NbSi6 pentagonal pyramids, and faces with five MoSi6 pentagonal pyramids. There are a spread of Nb–Si bond distances ranging from 2.57–2.90 Å. In the second Nb+2.60+ site, Nb+2.60+ is bonded to six Si4- atoms to form distorted NbSi6 pentagonal pyramids that share corners with two equivalent NbSi6 pentagonal pyramids, corners with thirteen MoSi6 pentagonal pyramids, corners with four equivalent NbSi4 tetrahedra, edges with three equivalent NbSi6 pentagonal pyramids, edges with two equivalent NbSi4 tetrahedra, faces with two equivalent NbSi6 pentagonal pyramids, and faces with five MoSi6 pentagonal pyramids. There are a spread of Nb–Si bond distances ranging from 2.59–2.89 Å. In the third Nb+2.60+ site, Nb+2.60+ is bonded to six Si4- atoms to form distorted NbSi6 pentagonal pyramids that share corners with six NbSi6 pentagonal pyramids, corners with nine MoSi6 pentagonal pyramids, corners with four equivalent NbSi4 tetrahedra, edges with three equivalent NbSi6 pentagonal pyramids, edges with two equivalent NbSi4 tetrahedra, and faces with seven MoSi6 pentagonal pyramids. There are a spread of Nb–Si bond distances ranging from 2.58–2.87 Å. In the fourth Nb+2.60+ site, Nb+2.60+ is bonded to four Si4- atoms to form distorted NbSi4 tetrahedra that share corners with six NbSi6 pentagonal pyramids, corners with ten MoSi6 pentagonal pyramids, edges with three NbSi6 pentagonal pyramids, edges with five MoSi6 pentagonal pyramids, and edges with two equivalent NbSi4 tetrahedra. There are a spread of Nb–Si bond distances ranging from 2.66–2.68 Å. There are five inequivalent Mo+2.20+ sites. In the first Mo+2.20+ site, Mo+2.20+ is bonded to six Si4- atoms to form distorted MoSi6 pentagonal pyramids that share corners with seven NbSi6 pentagonal pyramids, corners with eight MoSi6 pentagonal pyramids, corners with four equivalent NbSi4 tetrahedra, edges with three equivalent MoSi6 pentagonal pyramids, edges with two equivalent NbSi4 tetrahedra, faces with three MoSi6 pentagonal pyramids, and faces with four NbSi6 pentagonal pyramids. There are a spread of Mo–Si bond distances ranging from 2.57–2.90 Å. In the second Mo+2.20+ site, Mo+2.20+ is bonded to six Si4- atoms to form distorted MoSi6 pentagonal pyramids that share corners with seven NbSi6 pentagonal pyramids, corners with eight MoSi6 pentagonal pyramids, corners with four equivalent NbSi4 tetrahedra, edges with three equivalent MoSi6 pentagonal pyramids, edges with two equivalent NbSi4 tetrahedra, faces with three MoSi6 pentagonal pyramids, and faces with four NbSi6 pentagonal pyramids. There are a spread of Mo–Si bond distances ranging from 2.60–2.91 Å. In the third Mo+2.20+ site, Mo+2.20+ is bonded to six Si4- atoms to form distorted MoSi6 pentagonal pyramids that share corners with five NbSi6 pentagonal pyramids, corners with ten MoSi6 pentagonal pyramids, corners with four equivalent NbSi4 tetrahedra, edges with three equivalent MoSi6 pentagonal pyramids, edges with two equivalent NbSi4 tetrahedra, faces with three MoSi6 pentagonal pyramids, and faces with four NbSi6 pentagonal pyramids. There are a spread of Mo–Si bond distances ranging from 2.56–2.90 Å. In the fourth Mo+2.20+ site, Mo+2.20+ is bonded to six Si4- atoms to form distorted MoSi6 pentagonal pyramids that share corners with seven MoSi6 pentagonal pyramids, corners with eight NbSi6 pentagonal pyramids, corners with four equivalent NbSi4 tetrahedra, edges with three equivalent MoSi6 pentagonal pyramids, edges with two equivalent NbSi4 tetrahedra, faces with three NbSi6 pentagonal pyramids, and faces with four MoSi6 pentagonal pyramids. There are a spread of Mo–Si bond distances ranging from 2.57–2.89 Å. In the fifth Mo+2.20+ site, Mo+2.20+ is bonded to six Si4- atoms to form distorted MoSi6 pentagonal pyramids that share corners with four equivalent NbSi6 pentagonal pyramids, corners with eleven MoSi6 pentagonal pyramids, corners with four equivalent NbSi4 tetrahedra, edges with three equivalent NbSi6 pentagonal pyramids, edges with two equivalent NbSi4 tetrahedra, faces with two equivalent NbSi6 pentagonal pyramids, and faces with five MoSi6 pentagonal pyramids. There are a spread of Mo–Si bond distances ranging from 2.53–2.88 Å. There are five inequivalent Si4- sites. In the first Si4- site, Si4- is bonded in a 10-coordinate geometry to three Nb+2.60+, five Mo+2.20+, and two equivalent Si4- atoms. There are one shorter (2.50 Å) and one longer (2.54 Å) Si–Si bond lengths. In the second Si4- site, Si4- is bonded in a 10-coordinate geometry to four Nb+2.60+ and six Mo+2.20+ atoms. In the third Si4- site, Si4- is bonded in a 10-coordinate geometry to five Nb+2.60+ and five Mo+2.20+ atoms. In the fourth Si4- site, Si4- is bonded in a 10-coordinate geometry to five Nb+2.60+ and five Mo+2.20+ atoms. In the fifth Si4- site, Si4- is bonded in a 10-coordinate geometry to six Nb+2.60+ and four Mo+2.20+ atoms.