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DOE OSTI · 1726619

Materials Data on RbLiMg(BH4)4 by Materials Project

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Abstract

RbLiMg(BH4)4 crystallizes in the orthorhombic Aea2 space group. The structure is two-dimensional and consists of two RbLiMg(BH4)4 sheets oriented in the (1, 0, 0) direction. Rb1+ is bonded in a 6-coordinate geometry to six H+0.50+ atoms. There are a spread of Rb–H bond distances ranging from 2.82–3.02 Å. Li1+ is bonded in a 8-coordinate geometry to eight H+0.50+ atoms. There are a spread of Li–H bond distances ranging from 1.99–2.26 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 1.99–2.09 Å. There are two 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 1.21–1.24 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 is two shorter (1.22 Å) and two longer (1.23 Å) B–H bond length. There are eight inequivalent H+0.50+ sites. In the first H+0.50+ site, H+0.50+ is bonded in a distorted single-bond geometry to one Rb1+, one Li1+, 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. In the third H+0.50+ site, H+0.50+ is bonded in a distorted L-shaped geometry to one Mg2+ and one B3- atom. In the fourth H+0.50+ site, H+0.50+ is bonded in a water-like geometry to one Li1+ and one B3- atom. In the fifth H+0.50+ site, H+0.50+ is bonded in a single-bond geometry to one B3- atom. In the sixth H+0.50+ site, H+0.50+ is bonded in a 1-coordinate geometry to one Rb1+, one Li1+, one Mg2+, 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 distorted single-bond geometry to one Rb1+, one Li1+, and one B3- atom.

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36 MATERIALS SCIENCEB-H-Li-Mg-Rbcrystal structureRbLiMg(BH4)4

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2020-04-30. Materials Data on RbLiMg(BH4)4 by Materials Project. https://doi.org/10.17188/1726619

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36 MATERIALS SCIENCE↗