Materials Data on Nb2Se by Materials Project
Nb2Se crystallizes in the monoclinic C2/m space group. The structure is two-dimensional and consists of one Nb2Se sheet oriented in the (0, 0, 1) direction. there are four inequivalent Nb sites. In the first Nb site, Nb is bonded in a 3-coordinate geometry to three Se atoms. There are two shorter (2.73 Å) and one longer (2.83 Å) Nb–Se bond lengths. In the second Nb site, Nb is bonded to five Se atoms to form distorted edge-sharing NbSe5 trigonal bipyramids. There are a spread of Nb–Se bond distances ranging from 2.65–2.72 Å. In the third Nb site, Nb is bonded in a 2-coordinate geometry to two Se atoms. There are one shorter (2.83 Å) and one longer (2.93 Å) Nb–Se bond lengths. In the fourth Nb site, Nb is bonded in a distorted L-shaped geometry to two equivalent Se atoms. Both Nb–Se bond lengths are 2.65 Å. There are two inequivalent Se sites. In the first Se site, Se is bonded in a distorted hexagonal planar geometry to six Nb atoms. In the second Se site, Se is bonded in a 6-coordinate geometry to six Nb atoms.