DOI: 10.17188/1710969
title: Materials Data on K2Mg(BH4)4 by Materials Project

description: K2Mg(BH4)4 crystallizes in the monoclinic P2_1/c space group. The structure is three-dimensional. there are two inequivalent K1+ sites. In the first K1+ site, K1+ is bonded in a 8-coordinate geometry to eight H+0.50+ atoms. There are a spread of K–H bond distances ranging from 2.66–2.95 Å. In the second K1+ site, K1+ is bonded in a 8-coordinate geometry to eight H+0.50+ atoms. There are a spread of K–H bond distances ranging from 2.68–3.01 Å. Mg2+ is bonded to eight H+0.50+ atoms to form distorted MgH8 hexagonal bipyramids that share edges with four BH4 tetrahedra. There are a spread of Mg–H bond distances ranging from 2.00–2.16 Å. There are four inequivalent B3- sites. In the first B3- site, B3- is bonded to four H+0.50+ atoms to form BH4 tetrahedra that share an edgeedge with one MgH8 hexagonal bipyramid. There are a spread of B–H bond distances ranging from 1.22–1.24 Å. In the second B3- site, B3- is bonded to four H+0.50+ atoms to form BH4 tetrahedra that share an edgeedge with one MgH8 hexagonal bipyramid. There are a spread of B–H bond distances ranging from 1.22–1.24 Å. In the third B3- site, B3- is bonded to four H+0.50+ atoms to form BH4 tetrahedra that share an edgeedge with one MgH8 hexagonal bipyramid. There are a spread of B–H bond distances ranging from 1.22–1.24 Å. In the fourth B3- site, B3- is bonded to four H+0.50+ atoms to form BH4 tetrahedra that share an edgeedge with one MgH8 hexagonal bipyramid. There is two shorter (1.22 Å) and two longer (1.24 Å) B–H bond length. There are sixteen 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 a single-bond geometry to two K1+ and one B3- atom. In the third H+0.50+ site, H+0.50+ is bonded in an L-shaped geometry to one Mg2+ and one B3- atom. In the fourth H+0.50+ site, H+0.50+ is bonded in a single-bond geometry to two K1+ and one B3- atom. In the fifth H+0.50+ site, H+0.50+ is bonded in a distorted single-bond geometry to one K1+ and one B3- atom. In the sixth H+0.50+ site, H+0.50+ is bonded in a single-bond geometry to two equivalent K1+ and one B3- atom. In the seventh H+0.50+ site, H+0.50+ is bonded in an L-shaped geometry to one Mg2+ and one B3- atom. In the eighth H+0.50+ site, H+0.50+ is bonded in a 2-coordinate geometry to one K1+, one Mg2+, and one B3- atom. In the ninth H+0.50+ site, H+0.50+ is bonded in a distorted single-bond geometry to one K1+, one Mg2+, and one B3- atom. In the tenth H+0.50+ site, H+0.50+ is bonded in a distorted L-shaped geometry to one Mg2+ and one B3- atom. In the eleventh H+0.50+ site, H+0.50+ is bonded in a single-bond geometry to two K1+ and one B3- atom. In the twelfth H+0.50+ site, H+0.50+ is bonded in a single-bond geometry to one K1+ and one B3- atom. In the thirteenth H+0.50+ site, H+0.50+ is bonded in a distorted single-bond geometry to one K1+ and one B3- atom. In the fourteenth H+0.50+ site, H+0.50+ is bonded in a distorted single-bond geometry to two K1+ and one B3- atom. In the fifteenth H+0.50+ site, H+0.50+ is bonded in an L-shaped geometry to one Mg2+ and one B3- atom. In the sixteenth H+0.50+ site, H+0.50+ is bonded in a distorted single-bond geometry to one K1+, one Mg2+, and one B3- atom.