DOI: 10.17188/1739588
title: Materials Data on Nb2(AlGa)3 by Materials Project

description: Nb2(GaAl)3 crystallizes in the tetragonal P-4m2 space group. The structure is three-dimensional. Nb is bonded to six Ga and six Al atoms to form NbAl6Ga6 cuboctahedra that share corners with four equivalent NbAl6Ga6 cuboctahedra, corners with eight equivalent AlNb4Al2Ga6 cuboctahedra, edges with four equivalent AlNb4Al4Ga4 cuboctahedra, edges with eight equivalent NbAl6Ga6 cuboctahedra, edges with twelve GaNb4Al4Ga4 cuboctahedra, faces with four equivalent NbAl6Ga6 cuboctahedra, faces with six GaNb4Al4Ga4 cuboctahedra, and faces with eight AlNb4Al2Ga6 cuboctahedra. All Nb–Ga bond lengths are 2.90 Å. There are four shorter (2.71 Å) and two longer (2.90 Å) Nb–Al bond lengths. There are three inequivalent Ga sites. In the first Ga site, Ga is bonded to four equivalent Nb, four equivalent Ga, and four equivalent Al atoms to form GaNb4Al4Ga4 cuboctahedra that share corners with twelve GaNb4Al4Ga4 cuboctahedra, edges with eight equivalent NbAl6Ga6 cuboctahedra, edges with sixteen AlNb4Al2Ga6 cuboctahedra, faces with four equivalent NbAl6Ga6 cuboctahedra, faces with four equivalent AlNb4Al2Ga6 cuboctahedra, and faces with ten GaNb4Al4Ga4 cuboctahedra. All Ga–Ga bond lengths are 2.71 Å. All Ga–Al bond lengths are 2.91 Å. In the second Ga site, Ga is bonded to four equivalent Nb and eight Al atoms to form GaNb4Al8 cuboctahedra that share corners with twelve GaNb4Al4Ga4 cuboctahedra, edges with eight equivalent NbAl6Ga6 cuboctahedra, edges with eight equivalent GaNb4Al4Ga4 cuboctahedra, edges with eight equivalent AlNb4Al2Ga6 cuboctahedra, faces with four equivalent NbAl6Ga6 cuboctahedra, faces with six GaNb4Al4Ga4 cuboctahedra, and faces with eight AlNb4Al2Ga6 cuboctahedra. There are four shorter (2.71 Å) and four longer (2.89 Å) Ga–Al bond lengths. In the third Ga site, Ga is bonded to four equivalent Nb, four equivalent Ga, and four equivalent Al atoms to form GaNb4Al4Ga4 cuboctahedra that share corners with four equivalent GaNb4Al4Ga4 cuboctahedra, corners with eight equivalent AlNb4Al4Ga4 cuboctahedra, edges with eight equivalent NbAl6Ga6 cuboctahedra, edges with eight equivalent GaNb4Al8 cuboctahedra, edges with eight equivalent AlNb4Al2Ga6 cuboctahedra, faces with four equivalent NbAl6Ga6 cuboctahedra, faces with six AlNb4Al2Ga6 cuboctahedra, and faces with eight GaNb4Al4Ga4 cuboctahedra. All Ga–Al bond lengths are 2.91 Å. There are two inequivalent Al sites. In the first Al site, Al is bonded to four equivalent Nb, six Ga, and two equivalent Al atoms to form AlNb4Al2Ga6 cuboctahedra that share corners with four equivalent AlNb4Al2Ga6 cuboctahedra, corners with eight equivalent NbAl6Ga6 cuboctahedra, edges with twelve GaNb4Al4Ga4 cuboctahedra, edges with twelve AlNb4Al2Ga6 cuboctahedra, faces with six equivalent NbAl6Ga6 cuboctahedra, faces with six GaNb4Al4Ga4 cuboctahedra, and faces with six AlNb4Al2Ga6 cuboctahedra. Both Al–Al bond lengths are 2.89 Å. In the second Al site, Al is bonded to four equivalent Nb, four equivalent Ga, and four equivalent Al atoms to form distorted AlNb4Al4Ga4 cuboctahedra that share corners with four equivalent AlNb4Al4Ga4 cuboctahedra, corners with eight equivalent GaNb4Al4Ga4 cuboctahedra, edges with eight equivalent NbAl6Ga6 cuboctahedra, edges with eight equivalent GaNb4Al4Ga4 cuboctahedra, edges with eight equivalent AlNb4Al2Ga6 cuboctahedra, faces with four equivalent NbAl6Ga6 cuboctahedra, faces with six GaNb4Al8 cuboctahedra, and faces with eight AlNb4Al2Ga6 cuboctahedra.