Materials Data on Nb5(CuSi)4 by Materials Project
Nb5Cu4Si4 crystallizes in the tetragonal I4/m space group. The structure is three-dimensional. there are two inequivalent Nb+2.40+ sites. In the first Nb+2.40+ site, Nb+2.40+ is bonded in a square co-planar geometry to four equivalent Si4- atoms. All Nb–Si bond lengths are 2.66 Å. In the second Nb+2.40+ site, Nb+2.40+ is bonded to five equivalent Si4- atoms to form a mixture of distorted edge and corner-sharing NbSi5 trigonal bipyramids. There are a spread of Nb–Si bond distances ranging from 2.61–2.79 Å. Cu1+ is bonded in a distorted trigonal planar geometry to three equivalent Si4- atoms. There are two shorter (2.34 Å) and one longer (2.38 Å) Cu–Si bond lengths. Si4- is bonded in a 9-coordinate geometry to six Nb+2.40+ and three equivalent Cu1+ atoms.