Materials Data on Mg4AlB10 by Materials Project

Abstract

Mg4AlB10 is hexagonal omega structure-derived structured and crystallizes in the hexagonal P6/mmm space group. The structure is three-dimensional. there are two inequivalent Mg sites. In the first Mg site, Mg is bonded to twelve B atoms to form MgB12 cuboctahedra that share edges with six equivalent MgB12 cuboctahedra, edges with six equivalent AlB12 cuboctahedra, a faceface with one AlB12 cuboctahedra, and faces with seven MgB12 cuboctahedra. There are six shorter (2.47 Å) and six longer (2.56 Å) Mg–B bond lengths. In the second Mg site, Mg is bonded to twelve B atoms to form a mixture of face and edge-sharing MgB12 cuboctahedra. There are six shorter (2.47 Å) and six longer (2.49 Å) Mg–B bond lengths. Al is bonded to twelve equivalent B atoms to form AlB12 cuboctahedra that share edges with twelve equivalent MgB12 cuboctahedra, faces with two equivalent MgB12 cuboctahedra, and faces with six equivalent AlB12 cuboctahedra. All Al–B bond lengths are 2.38 Å. There are three inequivalent B sites. In the first B site, B is bonded in a 9-coordinate geometry to three equivalent Mg, three equivalent Al, and three equivalent B atoms. All B–B bond lengths are 1.77 Å. In the second B site, B is bonded in a 9-coordinate geometry to six Mg and three equivalent B atoms. All B–B bond lengths are 1.77 Å. In the third B site, B is bonded in a 9-coordinate geometry to six equivalent Mg and three equivalent B atoms. All B–B bond lengths are 1.77 Å.