Materials Data on La6Al5Fe9 by Materials Project

Abstract

La6Fe9Al5 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 6-coordinate geometry to one Fe and five Al atoms. The La–Fe bond length is 3.21 Å. There are a spread of La–Al bond distances ranging from 3.35–3.41 Å. In the second La site, La is bonded in a 5-coordinate geometry to eight Fe and five Al atoms. There are four shorter (3.13 Å) and four longer (3.27 Å) La–Fe bond lengths. There are four shorter (3.30 Å) and one longer (3.44 Å) La–Al bond lengths. There are three inequivalent Fe sites. In the first Fe site, Fe is bonded to two equivalent La, eight Fe, and two equivalent Al atoms to form FeLa2Al2Fe8 cuboctahedra that share corners with four FeLa2Al2Fe8 cuboctahedra, edges with four equivalent FeLa3Al3Fe6 cuboctahedra, and faces with fifteen FeLa2Al2Fe8 cuboctahedra. There are a spread of Fe–Fe bond distances ranging from 2.44–2.58 Å. Both Fe–Al bond lengths are 2.63 Å. In the second Fe site, Fe is bonded to three La, six Fe, and three equivalent Al atoms to form distorted FeLa3Al3Fe6 cuboctahedra that share corners with seven equivalent FeLa3Al3Fe6 cuboctahedra, edges with four equivalent FeLa2Al2Fe8 cuboctahedra, and faces with fourteen FeLa2Al2Fe8 cuboctahedra. There are one shorter (2.44 Å) and one longer (2.65 Å) Fe–Fe bond lengths. There are one shorter (2.53 Å) and two longer (2.61 Å) Fe–Al bond lengths. In the third Fe site, Fe is bonded to eight Fe and four equivalent Al atoms to form a mixture of face and corner-sharing FeAl4Fe8 cuboctahedra. All Fe–Al bond lengths are 2.58 Å. There are two inequivalent Al sites. In the first Al site, Al is bonded in a distorted q6 geometry to ten La atoms. In the second Al site, Al is bonded in a 12-coordinate geometry to five La, six Fe, and one Al atom. The Al–Al bond length is 2.75 Å.