Materials Data on CaNi5H by Materials Project

Abstract

CaNi5H crystallizes in the orthorhombic Cmmm space group. The structure is three-dimensional. Ca is bonded in a 2-coordinate geometry to eight equivalent Ni and two equivalent H atoms. All Ca–Ni bond lengths are 3.21 Å. Both Ca–H bond lengths are 2.45 Å. There are three inequivalent Ni sites. In the first Ni site, Ni is bonded in a single-bond geometry to four equivalent Ni and one H atom. All Ni–Ni bond lengths are 2.38 Å. The Ni–H bond length is 1.61 Å. In the second Ni site, Ni is bonded in a linear geometry to four equivalent Ni and two equivalent H atoms. All Ni–Ni bond lengths are 2.54 Å. Both Ni–H bond lengths are 1.95 Å. In the third Ni site, Ni is bonded to four equivalent Ca and eight Ni atoms to form NiCa4Ni8 cuboctahedra that share corners with twelve equivalent NiCa4Ni8 cuboctahedra, corners with four equivalent HCa2Ni4 octahedra, edges with six equivalent NiCa4Ni8 cuboctahedra, faces with six equivalent NiCa4Ni8 cuboctahedra, and faces with four equivalent HCa2Ni4 octahedra. The corner-sharing octahedral tilt angles are 68°. Both Ni–Ni bond lengths are 2.45 Å. H is bonded to two equivalent Ca and four Ni atoms to form HCa2Ni4 octahedra that share corners with eight equivalent NiCa4Ni8 cuboctahedra, corners with four equivalent HCa2Ni4 octahedra, and faces with eight equivalent NiCa4Ni8 cuboctahedra. The corner-sharing octahedral tilt angles are 0°.