Materials Data on La(Al2Fe)4 by Materials Project

Abstract

LaFe4Al8 crystallizes in the tetragonal I4/mmm space group. The structure is three-dimensional. La is bonded in a 12-coordinate geometry to eight equivalent Fe and twelve Al atoms. All La–Fe bond lengths are 3.37 Å. There are four shorter (3.04 Å) and eight longer (3.22 Å) La–Al bond lengths. Fe is bonded to two equivalent La, two equivalent Fe, and eight Al atoms to form a mixture of distorted corner, edge, and face-sharing FeLa2Al8Fe2 cuboctahedra. Both Fe–Fe bond lengths are 2.52 Å. There are four shorter (2.55 Å) and four longer (2.68 Å) Fe–Al bond lengths. There are two inequivalent Al sites. In the first Al site, Al is bonded in a 12-coordinate geometry to two equivalent La, four equivalent Fe, and six Al atoms. There are a spread of Al–Al bond distances ranging from 2.73–2.83 Å. In the second Al site, Al is bonded in a 10-coordinate geometry to one La, four equivalent Fe, and five Al atoms. The Al–Al bond length is 2.75 Å.