Materials Data on BaMg2H8Os by Materials Project

Abstract

BaMg2OsH8 crystallizes in the tetragonal P4_2/mmc space group. The structure is three-dimensional. Ba2+ is bonded to eight H+0.50- atoms to form BaH8 hexagonal bipyramids that share corners with four equivalent OsH6 octahedra and edges with four equivalent BaH8 hexagonal bipyramids. The corner-sharing octahedral tilt angles are 68°. There are four shorter (2.70 Å) and four longer (2.79 Å) Ba–H bond lengths. Mg2+ is bonded in a 6-coordinate geometry to six H+0.50- atoms. There are two shorter (1.96 Å) and four longer (2.14 Å) Mg–H bond lengths. Os2- is bonded to six H+0.50- atoms to form OsH6 octahedra that share corners with four equivalent BaH8 hexagonal bipyramids. There is two shorter (1.71 Å) and four longer (1.72 Å) Os–H bond length. There are three inequivalent H+0.50- sites. In the first H+0.50- site, H+0.50- is bonded in a T-shaped geometry to two equivalent Mg2+ and one Os2- atom. In the second H+0.50- site, H+0.50- is bonded in a distorted water-like geometry to two equivalent Ba2+ and two equivalent Mg2+ atoms. In the third H+0.50- site, H+0.50- is bonded in a distorted trigonal planar geometry to two equivalent Ba2+ and one Os2- atom.