Materials Data on PrMg2Ni9 by Materials Project

Abstract

PrMg2Ni9 crystallizes in the trigonal R-3m space group. The structure is three-dimensional. Mg is bonded in a 12-coordinate geometry to twelve Ni atoms. There are nine shorter (2.82 Å) and three longer (2.87 Å) Mg–Ni bond lengths. Pr is bonded in a distorted hexagonal planar geometry to eighteen Ni atoms. There are six shorter (2.83 Å) and twelve longer (3.17 Å) Pr–Ni bond lengths. There are three inequivalent Ni sites. In the first Ni site, Ni is bonded to three equivalent Mg, two equivalent Pr, and seven Ni atoms to form a mixture of corner, edge, and face-sharing NiPr2Mg3Ni7 cuboctahedra. There are a spread of Ni–Ni bond distances ranging from 2.39–2.47 Å. In the second Ni site, Ni is bonded in a 12-coordinate geometry to three equivalent Pr and nine Ni atoms. All Ni–Ni bond lengths are 2.83 Å. In the third Ni site, Ni is bonded to six equivalent Mg and six equivalent Ni atoms to form NiMg6Ni6 cuboctahedra that share corners with twelve equivalent NiPr2Mg3Ni7 cuboctahedra, edges with six equivalent NiMg6Ni6 cuboctahedra, and faces with eighteen equivalent NiPr2Mg3Ni7 cuboctahedra.