Materials Data on La5(AlBr)4 by Materials Project

Abstract

La5(AlBr)4 crystallizes in the tetragonal I4/mcm space group. The structure is three-dimensional. there are two inequivalent La sites. In the first La site, La is bonded in a distorted linear geometry to eight equivalent Al and two equivalent Br atoms. All La–Al bond lengths are 3.26 Å. Both La–Br bond lengths are 3.16 Å. In the second La site, La is bonded in a 6-coordinate geometry to four equivalent Al and five Br atoms. There are a spread of La–Al bond distances ranging from 3.15–3.37 Å. There are a spread of La–Br bond distances ranging from 3.15–3.45 Å. Al is bonded in a 9-coordinate geometry to six La and three equivalent Al atoms. There are two shorter (2.67 Å) and one longer (2.81 Å) Al–Al bond lengths. There are two inequivalent Br sites. In the first Br site, Br is bonded to six equivalent La atoms to form distorted BrLa6 pentagonal pyramids that share corners with four equivalent BrLa5 square pyramids, edges with four equivalent BrLa6 pentagonal pyramids, edges with four equivalent BrLa5 square pyramids, and a faceface with one BrLa6 pentagonal pyramid. In the second Br site, Br is bonded to five La atoms to form BrLa5 square pyramids that share corners with four equivalent BrLa6 pentagonal pyramids, corners with five equivalent BrLa5 square pyramids, and edges with four equivalent BrLa6 pentagonal pyramids.