Materials Data on MgB4Os3 by Materials Project

Abstract

MgOs3B4 crystallizes in the orthorhombic Cmcm space group. The structure is three-dimensional. Mg2+ is bonded in a 8-coordinate geometry to eight Os+0.67- atoms. There are four shorter (2.86 Å) and four longer (2.98 Å) Mg–Os bond lengths. There are two inequivalent Os+0.67- sites. In the first Os+0.67- site, Os+0.67- is bonded in a 6-coordinate geometry to two equivalent Mg2+ and six B atoms. There are a spread of Os–B bond distances ranging from 2.19–2.23 Å. In the second Os+0.67- site, Os+0.67- is bonded in a 10-coordinate geometry to four equivalent Mg2+ and six B atoms. There are a spread of Os–B bond distances ranging from 2.18–2.22 Å. There are three inequivalent B sites. In the first B site, B is bonded to six Os+0.67- atoms to form distorted BOs6 pentagonal pyramids that share corners with two equivalent BB4Os4 hexagonal bipyramids, edges with three equivalent BB4Os4 hexagonal bipyramids, and faces with two equivalent BOs6 pentagonal pyramids. In the second B site, B is bonded to four Os+0.67- and four equivalent B atoms to form distorted BB4Os4 hexagonal bipyramids that share corners with two equivalent BOs6 pentagonal pyramids, edges with three equivalent BOs6 pentagonal pyramids, and faces with two equivalent BB4Os4 hexagonal bipyramids. All B–B bond lengths are 2.00 Å. In the third B site, B is bonded in a 6-coordinate geometry to four Os+0.67- and two equivalent B atoms.