Materials Data on LaCo5H4 by Materials Project

Abstract

LaCo5H4 crystallizes in the orthorhombic Cmmm space group. The structure is three-dimensional. La is bonded in a 12-coordinate geometry to eight H atoms. There are four shorter (2.41 Å) and four longer (2.61 Å) La–H bond lengths. There are three inequivalent Co sites. In the first Co site, Co is bonded in a water-like geometry to two equivalent Co and two equivalent H atoms. Both Co–Co bond lengths are 2.35 Å. Both Co–H bond lengths are 1.71 Å. In the second Co site, Co is bonded in a distorted square co-planar geometry to two equivalent Co and four H atoms. Both Co–Co bond lengths are 2.61 Å. There is two shorter (1.64 Å) and two longer (2.02 Å) Co–H bond length. In the third Co site, Co is bonded in a 12-coordinate geometry to eight Co atoms. There are two inequivalent H sites. In the first H site, H is bonded to two equivalent La and two equivalent Co atoms to form HLa2Co2 tetrahedra that share corners with four equivalent HLa2Co4 octahedra, corners with six equivalent HLa2Co2 tetrahedra, edges with four equivalent HLa2Co4 octahedra, and an edgeedge with one HLa2Co2 tetrahedra. The corner-sharing octahedral tilt angles are 62°. In the second H site, H is bonded to two equivalent La and four Co atoms to form distorted HLa2Co4 octahedra that share corners with six equivalent HLa2Co4 octahedra, corners with four equivalent HLa2Co2 tetrahedra, edges with two equivalent HLa2Co4 octahedra, and edges with four equivalent HLa2Co2 tetrahedra. The corner-sharing octahedra tilt angles range from 0–63°.