Materials Data on KSrMg6 by Materials Project

Abstract

KSrMg6 crystallizes in the orthorhombic Amm2 space group. The structure is three-dimensional. K is bonded to two equivalent Sr and ten Mg atoms to form distorted KSr2Mg10 cuboctahedra that share corners with four equivalent SrK2Mg10 cuboctahedra, corners with six equivalent KSr2Mg10 cuboctahedra, edges with two equivalent SrK2Mg10 cuboctahedra, faces with two equivalent KSr2Mg10 cuboctahedra, and faces with two equivalent SrK2Mg10 cuboctahedra. Both K–Sr bond lengths are 3.81 Å. There are a spread of K–Mg bond distances ranging from 3.45–3.54 Å. Sr is bonded to two equivalent K and ten Mg atoms to form distorted SrK2Mg10 cuboctahedra that share corners with four equivalent KSr2Mg10 cuboctahedra, corners with six equivalent SrK2Mg10 cuboctahedra, edges with two equivalent KSr2Mg10 cuboctahedra, faces with two equivalent KSr2Mg10 cuboctahedra, and faces with two equivalent SrK2Mg10 cuboctahedra. There are a spread of Sr–Mg bond distances ranging from 3.45–3.55 Å. There are four inequivalent Mg sites. In the first Mg site, Mg is bonded in a 10-coordinate geometry to two equivalent K, two equivalent Sr, and six Mg atoms. There are a spread of Mg–Mg bond distances ranging from 3.32–3.46 Å. In the second Mg site, Mg is bonded in a 8-coordinate geometry to two equivalent K, two equivalent Sr, and four Mg atoms. There are one shorter (3.20 Å) and one longer (3.24 Å) Mg–Mg bond lengths. In the third Mg site, Mg is bonded in a 2-coordinate geometry to two equivalent K and six Mg atoms. In the fourth Mg site, Mg is bonded in a 2-coordinate geometry to two equivalent Sr and six Mg atoms.