Materials Data on CaNi5H by Materials Project

Abstract

CaNi5H crystallizes in the orthorhombic Amm2 space group. The structure is three-dimensional. Ca is bonded in a distorted bent 120 degrees geometry to ten Ni and two equivalent H atoms. There are a spread of Ca–Ni bond distances ranging from 2.84–3.19 Å. Both Ca–H bond lengths are 2.33 Å. There are four inequivalent Ni sites. In the first Ni site, Ni is bonded in a 12-coordinate geometry to three equivalent Ca and nine Ni atoms. There are a spread of Ni–Ni bond distances ranging from 2.39–2.92 Å. In the second Ni site, Ni is bonded in a 12-coordinate geometry to three equivalent Ca and nine Ni atoms. All Ni–Ni bond lengths are 2.43 Å. In the third Ni site, Ni is bonded to four equivalent Ca and eight Ni atoms to form distorted NiCa4Ni8 cuboctahedra that share corners with eight equivalent NiCa4Ni8 cuboctahedra, corners with four equivalent HCa2Ni2 tetrahedra, edges with two equivalent NiCa4Ni8 cuboctahedra, an edgeedge with one HCa2Ni2 tetrahedra, faces with two equivalent NiCa4Ni8 cuboctahedra, and faces with two equivalent HCa2Ni2 tetrahedra. All Ni–Ni bond lengths are 2.47 Å. In the fourth Ni site, Ni is bonded in a single-bond geometry to six Ni and one H atom. The Ni–H bond length is 1.56 Å. H is bonded to two equivalent Ca and two equivalent Ni atoms to form HCa2Ni2 tetrahedra that share corners with four equivalent NiCa4Ni8 cuboctahedra, corners with two equivalent HCa2Ni2 tetrahedra, an edgeedge with one NiCa4Ni8 cuboctahedra, and faces with two equivalent NiCa4Ni8 cuboctahedra.