Materials Data on U(AlFe)6 by Materials Project
UFe6Al6 crystallizes in the orthorhombic Immm space group. The structure is three-dimensional. U is bonded in a 12-coordinate geometry to twelve Fe and eight Al atoms. There are four shorter (3.16 Å) and eight longer (3.28 Å) U–Fe bond lengths. There are a spread of U–Al bond distances ranging from 2.91–3.02 Å. There are two inequivalent Fe sites. In the first Fe site, Fe is bonded in a 12-coordinate geometry to two equivalent U, four Fe, and six Al atoms. There are two shorter (2.47 Å) and two longer (2.50 Å) Fe–Fe bond lengths. There are two shorter (2.50 Å) and four longer (2.61 Å) Fe–Al bond lengths. In the second Fe site, Fe is bonded to two equivalent U, four equivalent Fe, and six Al atoms to form a mixture of distorted corner, edge, and face-sharing FeU2Al6Fe4 cuboctahedra. There are two shorter (2.62 Å) and four longer (2.64 Å) Fe–Al bond lengths. There are three inequivalent Al sites. In the first Al site, Al is bonded in a 10-coordinate geometry to one U, six Fe, and three Al atoms. There are one shorter (2.62 Å) and two longer (2.79 Å) Al–Al bond lengths. In the second Al site, Al is bonded in a 8-coordinate geometry to one U, six Fe, and three Al atoms. There are one shorter (2.69 Å) and two longer (2.93 Å) Al–Al bond lengths. In the third Al site, Al is bonded in a 12-coordinate geometry to two equivalent U, six Fe, and four Al atoms.