Materials Data on Ca4Mg4Fe3H22 by Materials Project
Ca4Mg4Fe3H22 crystallizes in the cubic P-43m space group. The structure is three-dimensional. Ca2+ is bonded in a 9-coordinate geometry to nine H1- atoms. There are three shorter (2.38 Å) and six longer (2.42 Å) Ca–H bond lengths. Mg2+ is bonded in a 1-coordinate geometry to four H1- atoms. There is one shorter (1.86 Å) and three longer (2.04 Å) Mg–H bond length. Fe2+ is bonded in an octahedral geometry to six H1- atoms. All Fe–H bond lengths are 1.58 Å. There are three inequivalent H1- sites. In the first H1- site, H1- is bonded in a distorted single-bond geometry to two equivalent Ca2+ and one Fe2+ atom. In the second H1- site, H1- is bonded in a distorted T-shaped geometry to two equivalent Mg2+ and one Fe2+ atom. In the third H1- site, H1- is bonded to three equivalent Ca2+ and one Mg2+ atom to form distorted edge-sharing HCa3Mg tetrahedra.