Materials Data on MgNb2 by Materials Project

Abstract

MgNb2 is beta-derived structured and crystallizes in the trigonal R-3m space group. The structure is three-dimensional. Mg is bonded to six equivalent Mg and six equivalent Nb atoms to form MgMg6Nb6 cuboctahedra that share corners with six equivalent MgMg6Nb6 cuboctahedra, corners with twelve equivalent NbMg3Nb9 cuboctahedra, edges with six equivalent MgMg6Nb6 cuboctahedra, edges with twelve equivalent NbMg3Nb9 cuboctahedra, faces with six equivalent MgMg6Nb6 cuboctahedra, and faces with fourteen equivalent NbMg3Nb9 cuboctahedra. All Mg–Mg bond lengths are 2.92 Å. All Mg–Nb bond lengths are 3.10 Å. Nb is bonded to three equivalent Mg and nine equivalent Nb atoms to form NbMg3Nb9 cuboctahedra that share corners with six equivalent MgMg6Nb6 cuboctahedra, corners with nine equivalent NbMg3Nb9 cuboctahedra, edges with six equivalent MgMg6Nb6 cuboctahedra, edges with fifteen equivalent NbMg3Nb9 cuboctahedra, faces with seven equivalent MgMg6Nb6 cuboctahedra, and faces with twelve equivalent NbMg3Nb9 cuboctahedra. There are six shorter (2.92 Å) and three longer (3.09 Å) Nb–Nb bond lengths.