Materials Data on Tb(Al2Fe)4 by Materials Project
TbFe4Al8 crystallizes in the tetragonal I4/mmm space group. The structure is three-dimensional. Tb is bonded in a 12-coordinate geometry to eight equivalent Fe and twelve Al atoms. All Tb–Fe bond lengths are 3.33 Å. There are four shorter (2.97 Å) and eight longer (3.17 Å) Tb–Al bond lengths. Fe is bonded to two equivalent Tb, two equivalent Fe, and eight Al atoms to form a mixture of distorted edge, face, and corner-sharing FeTb2Al8Fe2 cuboctahedra. Both Fe–Fe bond lengths are 2.51 Å. There are four shorter (2.53 Å) and four longer (2.63 Å) Fe–Al bond lengths. There are two inequivalent Al sites. In the first Al site, Al is bonded in a 5-coordinate geometry to one Tb, four equivalent Fe, and five Al atoms. There are a spread of Al–Al bond distances ranging from 2.72–2.80 Å. In the second Al site, Al is bonded in a 12-coordinate geometry to two equivalent Tb, four equivalent Fe, and six Al atoms. Both Al–Al bond lengths are 2.72 Å.