Materials Data on BaAl9Ni2 by Materials Project

Abstract

BaNi2Al9 crystallizes in the hexagonal P6/mmm space group. The structure is three-dimensional. Ba is bonded to twelve equivalent Al atoms to form face-sharing BaAl12 cuboctahedra. All Ba–Al bond lengths are 3.55 Å. Ni is bonded in a 9-coordinate geometry to nine Al atoms. There are three shorter (2.30 Å) and six longer (2.58 Å) Ni–Al bond lengths. There are two inequivalent Al sites. In the first Al site, Al is bonded in a linear geometry to two equivalent Ni and eight equivalent Al atoms. All Al–Al bond lengths are 2.86 Å. In the second Al site, Al is bonded in a 2-coordinate geometry to two equivalent Ba, two equivalent Ni, and eight Al atoms. There are two shorter (2.86 Å) and two longer (2.95 Å) Al–Al bond lengths.