Materials Data on MgSn2 by Materials Project

Abstract

MgSn2 crystallizes in the hexagonal P-62m space group. The structure is three-dimensional. Mg is bonded to nine Sn atoms to form distorted MgSn9 cuboctahedra that share corners with six equivalent SnMg6Sn6 cuboctahedra, corners with fifteen equivalent MgSn9 cuboctahedra, edges with three equivalent SnMg6Sn6 cuboctahedra, and faces with five equivalent MgSn9 cuboctahedra. There are six shorter (3.27 Å) and three longer (3.37 Å) Mg–Sn bond lengths. There are two inequivalent Sn sites. In the first Sn site, Sn is bonded in a 12-coordinate geometry to four equivalent Mg and two equivalent Sn atoms. Both Sn–Sn bond lengths are 3.30 Å. In the second Sn site, Sn is bonded to six equivalent Mg and six equivalent Sn atoms to form distorted SnMg6Sn6 cuboctahedra that share corners with twelve equivalent MgSn9 cuboctahedra, edges with six equivalent MgSn9 cuboctahedra, edges with six equivalent SnMg6Sn6 cuboctahedra, and faces with two equivalent SnMg6Sn6 cuboctahedra.