Materials Data on Th2Ni7 by Materials Project

Abstract

Th2Ni7 crystallizes in the hexagonal P6_3/mmc space group. The structure is three-dimensional. there are two inequivalent Th sites. In the first Th site, Th is bonded in a 6-coordinate geometry to eighteen Ni atoms. There are a spread of Th–Ni bond distances ranging from 2.88–3.34 Å. In the second Th site, Th is bonded in a 12-coordinate geometry to twelve Ni atoms. There are a spread of Th–Ni bond distances ranging from 2.82–3.24 Å. There are five inequivalent Ni sites. In the first Ni site, Ni is bonded in a 12-coordinate geometry to three equivalent Th and nine Ni atoms. There are a spread of Ni–Ni bond distances ranging from 2.48–2.87 Å. In the second Ni site, Ni is bonded to four equivalent Th and eight Ni atoms to form a mixture of corner, edge, and face-sharing NiTh4Ni8 cuboctahedra. There are four shorter (2.49 Å) and two longer (2.50 Å) Ni–Ni bond lengths. In the third Ni site, Ni is bonded to five Th and seven Ni atoms to form a mixture of distorted corner, edge, and face-sharing NiTh5Ni7 cuboctahedra. There are a spread of Ni–Ni bond distances ranging from 2.48–2.56 Å. In the fourth Ni site, Ni is bonded to six equivalent Th and six equivalent Ni atoms to form NiTh6Ni6 cuboctahedra that share corners with twelve equivalent NiTh5Ni7 cuboctahedra, edges with six equivalent NiTh6Ni6 cuboctahedra, and faces with eighteen equivalent NiTh5Ni7 cuboctahedra. In the fifth Ni site, Ni is bonded in a 12-coordinate geometry to three equivalent Th and nine Ni atoms.