Materials Data on Nb3(CuSe3)2 by Materials Project

Nb3(CuSe3)2 crystallizes in the monoclinic P2_1 space group. The structure is three-dimensional. there are three inequivalent Nb+3.33+ sites. In the first Nb+3.33+ site, Nb+3.33+ is bonded to six Se2- atoms to form distorted NbSe6 pentagonal pyramids that share corners with six CuSe4 trigonal pyramids, edges with six NbSe6 pentagonal pyramids, and a faceface with one CuSe4 trigonal pyramid. There are a spread of Nb–Se bond distances ranging from 2.59–2.69 Å. In the second Nb+3.33+ site, Nb+3.33+ is bonded to six Se2- atoms to form distorted NbSe6 pentagonal pyramids that share corners with seven CuSe4 trigonal pyramids and edges with six NbSe6 pentagonal pyramids. There are a spread of Nb–Se bond distances ranging from 2.61–2.64 Å. In the third Nb+3.33+ site, Nb+3.33+ is bonded to six Se2- atoms to form distorted NbSe6 pentagonal pyramids that share corners with five CuSe4 trigonal pyramids, edges with six NbSe6 pentagonal pyramids, and a faceface with one CuSe4 trigonal pyramid. There are a spread of Nb–Se bond distances ranging from 2.62–2.69 Å. There are two inequivalent Cu1+ sites. In the first Cu1+ site, Cu1+ is bonded to four Se2- atoms to form distorted CuSe4 trigonal pyramids that share corners with nine NbSe6 pentagonal pyramids, corners with two equivalent CuSe4 trigonal pyramids, and a faceface with one NbSe6 pentagonal pyramid. There are one shorter (2.37 Å) and three longer (2.43 Å) Cu–Se bond lengths. In the second Cu1+ site, Cu1+ is bonded to four Se2- atoms to form distorted CuSe4 trigonal pyramids that share corners with nine NbSe6 pentagonal pyramids, corners with two equivalent CuSe4 trigonal pyramids, and a faceface with one NbSe6 pentagonal pyramid. There are a spread of Cu–Se bond distances ranging from 2.36–2.43 Å. There are six inequivalent Se2- sites. In the first Se2- site, Se2- is bonded in a 5-coordinate geometry to three Nb+3.33+ and two equivalent Cu1+ atoms. In the second Se2- site, Se2- is bonded in a distorted rectangular see-saw-like geometry to three Nb+3.33+ and one Cu1+ atom. In the third Se2- site, Se2- is bonded in a distorted rectangular see-saw-like geometry to three Nb+3.33+ and one Cu1+ atom. In the fourth Se2- site, Se2- is bonded in a rectangular see-saw-like geometry to three Nb+3.33+ and one Cu1+ atom. In the fifth Se2- site, Se2- is bonded in a distorted rectangular see-saw-like geometry to three Nb+3.33+ and one Cu1+ atom. In the sixth Se2- site, Se2- is bonded in a 5-coordinate geometry to three Nb+3.33+ and two equivalent Cu1+ atoms.