Materials Data on SrMgH4 by Materials Project
SrMgH4 crystallizes in the orthorhombic Cmc2_1 space group. The structure is three-dimensional. Sr2+ is bonded in a 9-coordinate geometry to nine H1- atoms. There are a spread of Sr–H bond distances ranging from 2.44–2.80 Å. Mg2+ is bonded to six H1- atoms to form corner-sharing MgH6 octahedra. The corner-sharing octahedra tilt angles range from 14–44°. There are a spread of Mg–H bond distances ranging from 1.89–2.02 Å. There are four inequivalent H1- sites. In the first H1- site, H1- is bonded in a 1-coordinate geometry to three equivalent Sr2+ and one Mg2+ atom. In the second H1- site, H1- is bonded to three equivalent Sr2+ and one Mg2+ atom to form distorted corner-sharing HSr3Mg trigonal pyramids. In the third H1- site, H1- is bonded in a distorted T-shaped geometry to one Sr2+ and two equivalent Mg2+ atoms. In the fourth H1- site, H1- is bonded in a 4-coordinate geometry to two equivalent Sr2+ and two equivalent Mg2+ atoms.