Materials Data on Ca4(H4Rh)3 by Materials Project

Abstract

Ca4(RhH4)3 crystallizes in the cubic Im-3m space group. The structure is three-dimensional. Ca is bonded to twelve H atoms to form CaH12 cuboctahedra that share corners with twelve equivalent CaH12 cuboctahedra, faces with six equivalent CaH12 cuboctahedra, and faces with six equivalent RhH6 octahedra. All Ca–H bond lengths are 2.58 Å. Rh is bonded to six H atoms to form RhH6 octahedra that share corners with four equivalent RhH6 octahedra and faces with eight equivalent CaH12 cuboctahedra. The corner-sharing octahedral tilt angles are 0°. There is two shorter (1.71 Å) and four longer (1.82 Å) Rh–H bond length. There are two inequivalent H sites. In the first H site, H is bonded to four equivalent Ca and one Rh atom to form HCa4Rh square pyramids that share corners with eight equivalent HCa4Rh2 octahedra, corners with thirteen equivalent HCa4Rh square pyramids, edges with four equivalent HCa4Rh2 octahedra, edges with four equivalent HCa4Rh square pyramids, and faces with four equivalent HCa4Rh2 octahedra. The corner-sharing octahedral tilt angles are 58°. In the second H site, H is bonded to four equivalent Ca and two equivalent Rh atoms to form HCa4Rh2 octahedra that share corners with fourteen equivalent HCa4Rh2 octahedra, corners with eight equivalent HCa4Rh square pyramids, edges with four equivalent HCa4Rh square pyramids, faces with four equivalent HCa4Rh2 octahedra, and faces with four equivalent HCa4Rh square pyramids. The corner-sharing octahedra tilt angles range from 0–60°.