Materials Data on CaAlH5 by Materials Project

Abstract

CaAlH5 crystallizes in the monoclinic P2_1/c space group. The structure is three-dimensional. there are two inequivalent Ca2+ sites. In the first Ca2+ site, Ca2+ is bonded in a 7-coordinate geometry to eight H1- atoms. There are a spread of Ca–H bond distances ranging from 2.16–2.69 Å. In the second Ca2+ site, Ca2+ is bonded in a 5-coordinate geometry to five H1- atoms. There are a spread of Ca–H bond distances ranging from 2.14–2.25 Å. There are two inequivalent Al3+ sites. In the first Al3+ site, Al3+ is bonded to five H1- atoms to form distorted corner-sharing AlH5 trigonal bipyramids. There are a spread of Al–H bond distances ranging from 1.64–1.94 Å. In the second Al3+ site, Al3+ is bonded to four H1- atoms to form corner-sharing AlH4 tetrahedra. There are a spread of Al–H bond distances ranging from 1.61–1.70 Å. There are ten inequivalent H1- sites. In the first H1- site, H1- is bonded in a distorted water-like geometry to one Ca2+ and one Al3+ atom. In the second H1- site, H1- is bonded in a water-like geometry to one Ca2+ and one Al3+ atom. In the third H1- site, H1- is bonded in a single-bond geometry to one Al3+ atom. In the fourth H1- site, H1- is bonded in a water-like geometry to one Ca2+ and one Al3+ atom. In the fifth H1- site, H1- is bonded in a distorted bent 120 degrees geometry to one Ca2+ and one Al3+ atom. In the sixth H1- site, H1- is bonded in a distorted trigonal non-coplanar geometry to three Ca2+ atoms. In the seventh H1- site, H1- is bonded in a distorted single-bond geometry to two equivalent Ca2+ and one Al3+ atom. In the eighth H1- site, H1- is bonded in a distorted bent 120 degrees geometry to two Al3+ atoms. In the ninth H1- site, H1- is bonded in a distorted trigonal non-coplanar geometry to three Ca2+ atoms. In the tenth H1- site, H1- is bonded in a bent 120 degrees geometry to one Ca2+ and one Al3+ atom.