Materials Data on Sm(MgSb)2 by Materials Project

Abstract

SmMg2Sb2 crystallizes in the trigonal P-3m1 space group. The structure is three-dimensional. Mg2+ is bonded to four equivalent Sb3- atoms to form MgSb4 tetrahedra that share corners with six equivalent SmSb6 octahedra, corners with six equivalent MgSb4 tetrahedra, edges with three equivalent SmSb6 octahedra, and edges with three equivalent MgSb4 tetrahedra. The corner-sharing octahedra tilt angles range from 16–57°. There are three shorter (2.84 Å) and one longer (2.91 Å) Mg–Sb bond lengths. Sm2+ is bonded to six equivalent Sb3- atoms to form SmSb6 octahedra that share corners with twelve equivalent MgSb4 tetrahedra, edges with six equivalent SmSb6 octahedra, and edges with six equivalent MgSb4 tetrahedra. All Sm–Sb bond lengths are 3.25 Å. Sb3- is bonded to four equivalent Mg2+ and three equivalent Sm2+ atoms to form a mixture of distorted corner and edge-sharing SbSm3Mg4 pentagonal bipyramids.