Materials Data on Nb4Al by Materials Project
Nb4Al crystallizes in the orthorhombic Fmmm space group. The structure is three-dimensional. there are two inequivalent Nb sites. In the first Nb site, Nb is bonded in a 8-coordinate geometry to six Nb and four equivalent Al atoms. There are four shorter (2.83 Å) and two longer (2.94 Å) Nb–Nb bond lengths. There are two shorter (2.80 Å) and two longer (3.16 Å) Nb–Al bond lengths. In the second Nb site, Nb is bonded in a distorted body-centered cubic geometry to eight Nb atoms. There are four shorter (2.83 Å) and two longer (2.90 Å) Nb–Nb bond lengths. Al is bonded to eight equivalent Nb and four equivalent Al atoms to form a mixture of distorted corner and face-sharing AlNb8Al4 cuboctahedra. All Al–Al bond lengths are 2.83 Å.