Materials Data on Sm2Co17H3 by Materials Project

Abstract

Sm2Co17H3 crystallizes in the trigonal R-3m space group. The structure is three-dimensional. Sm is bonded in a distorted trigonal planar geometry to four Co and three equivalent H atoms. There are one shorter (3.02 Å) and three longer (3.26 Å) Sm–Co bond lengths. All Sm–H bond lengths are 2.44 Å. There are four inequivalent Co sites. In the first Co site, Co is bonded to two equivalent Sm and ten Co atoms to form distorted CoSm2Co10 cuboctahedra that share corners with four equivalent CoSm2Co10 cuboctahedra, corners with two equivalent HSm2Co4 octahedra, faces with four equivalent CoSm2Co10 cuboctahedra, and faces with four equivalent HSm2Co4 octahedra. The corner-sharing octahedral tilt angles are 45°. There are a spread of Co–Co bond distances ranging from 2.38–2.58 Å. In the second Co site, Co is bonded in a single-bond geometry to four Co and one H atom. Both Co–Co bond lengths are 2.66 Å. The Co–H bond length is 1.84 Å. In the third Co site, Co is bonded in a single-bond geometry to three Co and one H atom. The Co–Co bond length is 2.60 Å. The Co–H bond length is 1.84 Å. In the fourth Co site, Co is bonded in a 2-coordinate geometry to one Sm and thirteen Co atoms. The Co–Co bond length is 2.34 Å. H is bonded to two equivalent Sm and four Co atoms to form HSm2Co4 octahedra that share corners with two equivalent CoSm2Co10 cuboctahedra, corners with four equivalent HSm2Co4 octahedra, and faces with four equivalent CoSm2Co10 cuboctahedra. The corner-sharing octahedral tilt angles are 60°.