Materials Data on Mg(BH4)2 by Materials Project

Abstract

Mg(BH4)2 crystallizes in the tetragonal I4_1/acd space group. The structure is three-dimensional and consists of two Mg(BH4)2 frameworks. Mg2+ is bonded to eight H+0.50+ atoms to form MgH8 hexagonal bipyramids that share edges with four equivalent BH4 tetrahedra. There are four shorter (2.08 Å) and four longer (2.12 Å) Mg–H bond lengths. B3- is bonded to four H+0.50+ atoms to form BH4 tetrahedra that share edges with two equivalent MgH8 hexagonal bipyramids. There is two shorter (1.22 Å) and two longer (1.23 Å) B–H bond length. There are two inequivalent H+0.50+ sites. In the first H+0.50+ site, H+0.50+ is bonded in an L-shaped geometry to one Mg2+ and one B3- atom. In the second H+0.50+ site, H+0.50+ is bonded in an L-shaped geometry to one Mg2+ and one B3- atom.