Materials Data on Ca(MgSb)2 by Materials Project

Abstract

Ca(MgSb)2 crystallizes in the trigonal P-3m1 space group. The structure is three-dimensional. Ca2+ is bonded to six equivalent Sb3- atoms to form CaSb6 octahedra that share corners with twelve equivalent MgSb4 tetrahedra, edges with six equivalent CaSb6 octahedra, and edges with six equivalent MgSb4 tetrahedra. All Ca–Sb bond lengths are 3.28 Å. Mg2+ is bonded to four equivalent Sb3- atoms to form MgSb4 tetrahedra that share corners with six equivalent CaSb6 octahedra, corners with six equivalent MgSb4 tetrahedra, edges with three equivalent CaSb6 octahedra, and edges with three equivalent MgSb4 tetrahedra. The corner-sharing octahedra tilt angles range from 15–56°. There are three shorter (2.87 Å) and one longer (2.94 Å) Mg–Sb bond lengths. Sb3- is bonded to three equivalent Ca2+ and four equivalent Mg2+ atoms to form a mixture of distorted edge and corner-sharing SbCa3Mg4 pentagonal bipyramids.