Materials Data on SrAlH5 by Materials Project

Abstract

SrAlH5 crystallizes in the orthorhombic P2_12_12_1 space group. The structure is three-dimensional. Sr2+ is bonded to twelve H1- atoms to form distorted SrH12 cuboctahedra that share corners with four equivalent SrH12 cuboctahedra, corners with two equivalent AlH6 octahedra, edges with four equivalent SrH12 cuboctahedra, an edgeedge with one AlH6 octahedra, faces with two equivalent SrH12 cuboctahedra, and faces with three equivalent AlH6 octahedra. The corner-sharing octahedra tilt angles range from 46–49°. There are a spread of Sr–H bond distances ranging from 2.47–2.83 Å. Al3+ is bonded to six H1- atoms to form AlH6 octahedra that share corners with two equivalent SrH12 cuboctahedra, corners with two equivalent AlH6 octahedra, an edgeedge with one SrH12 cuboctahedra, and faces with three equivalent SrH12 cuboctahedra. The corner-sharing octahedral tilt angles are 42°. There are a spread of Al–H bond distances ranging from 1.70–1.82 Å. There are five inequivalent H1- sites. In the first H1- site, H1- is bonded in a distorted single-bond geometry to two equivalent Sr2+ and one Al3+ atom. In the second H1- site, H1- is bonded in a 1-coordinate geometry to three equivalent Sr2+ and one Al3+ atom. In the third H1- site, H1- is bonded in a distorted single-bond geometry to three equivalent Sr2+ and one Al3+ atom. In the fourth H1- site, H1- is bonded in a distorted single-bond geometry to three equivalent Sr2+ and one Al3+ atom. In the fifth H1- site, H1- is bonded in a 2-coordinate geometry to one Sr2+ and two equivalent Al3+ atoms.