Materials Data on CaAl9Ni by Materials Project

Abstract

Al9NiCa crystallizes in the hexagonal P6_3/mmc space group. The structure is three-dimensional. Ca is bonded to twelve equivalent Al atoms to form distorted face-sharing CaAl12 cuboctahedra. There are six shorter (3.30 Å) and six longer (3.45 Å) Ca–Al bond lengths. Ni is bonded in a 9-coordinate geometry to nine Al atoms. There are six shorter (2.48 Å) and three longer (2.50 Å) Ni–Al bond lengths. There are two inequivalent Al sites. In the first Al site, Al is bonded in a 1-coordinate geometry to two equivalent Ca, one Ni, and eight Al atoms. There are a spread of Al–Al bond distances ranging from 2.74–2.88 Å. In the second Al site, Al is bonded in a distorted single-bond geometry to one Ni and eight equivalent Al atoms.