Materials Data on MgGa by Materials Project

Abstract

MgGa crystallizes in the hexagonal P-6m2 space group. The structure is three-dimensional. there are two inequivalent Mg sites. In the first Mg site, Mg is bonded to nine Mg and three equivalent Ga atoms to form distorted MgMg9Ga3 cuboctahedra that share corners with six equivalent GaGa12 cuboctahedra, corners with twelve equivalent MgMg9Ga3 cuboctahedra, edges with twelve MgMg9Ga3 cuboctahedra, a faceface with one GaGa12 cuboctahedra, and faces with thirteen MgMg9Ga3 cuboctahedra. There are six shorter (3.07 Å) and three longer (3.20 Å) Mg–Mg bond lengths. All Mg–Ga bond lengths are 3.01 Å. In the second Mg site, Mg is bonded to twelve Mg atoms to form MgMg12 cuboctahedra that share corners with six equivalent MgMg12 cuboctahedra, edges with eighteen MgMg9Ga3 cuboctahedra, and faces with eighteen MgMg9Ga3 cuboctahedra. All Mg–Mg bond lengths are 3.07 Å. There are two inequivalent Ga sites. In the first Ga site, Ga is bonded to twelve Ga atoms to form GaGa12 cuboctahedra that share corners with six equivalent GaGa12 cuboctahedra, corners with twelve equivalent MgMg9Ga3 cuboctahedra, edges with six equivalent GaGa12 cuboctahedra, faces with two equivalent MgMg9Ga3 cuboctahedra, and faces with six equivalent GaGa12 cuboctahedra. There are six shorter (3.07 Å) and six longer (3.12 Å) Ga–Ga bond lengths. In the second Ga site, Ga is bonded in a 12-coordinate geometry to three equivalent Mg and three equivalent Ga atoms.