Materials Data on LaFe9Si4 by Materials Project

Abstract

LaFe9Si4 crystallizes in the tetragonal I4/mcm space group. The structure is three-dimensional. La is bonded in a 8-coordinate geometry to sixteen Fe and eight equivalent Si atoms. There are eight shorter (3.25 Å) and eight longer (3.34 Å) La–Fe bond lengths. All La–Si bond lengths are 3.28 Å. There are three inequivalent Fe sites. In the first Fe site, Fe is bonded to two equivalent La, six Fe, and four equivalent Si atoms to form a mixture of distorted face and corner-sharing FeLa2Fe6Si4 cuboctahedra. There are a spread of Fe–Fe bond distances ranging from 2.36–2.61 Å. There are two shorter (2.49 Å) and two longer (2.54 Å) Fe–Si bond lengths. In the second Fe site, Fe is bonded in a 12-coordinate geometry to two equivalent La, six Fe, and four equivalent Si atoms. There are a spread of Fe–Fe bond distances ranging from 2.47–2.66 Å. There are a spread of Fe–Si bond distances ranging from 2.39–2.47 Å. In the third Fe site, Fe is bonded to eight Fe and four equivalent Si atoms to form a mixture of face and corner-sharing FeFe8Si4 cuboctahedra. All Fe–Si bond lengths are 2.41 Å. Si is bonded in a 12-coordinate geometry to two equivalent La, nine Fe, and one Si atom. The Si–Si bond length is 2.79 Å.