DOE OSTI2020
UAl2 is Hexagonal Laves structured and crystallizes in the hexagonal P6_3/mmc space group. The structure is three-dimensional. there are two inequivalent U sites. In the first U site, U is bonded in a 1-coordinate geometry to one U and twelve Al atoms. The U–U bond length is 2.62 Å. There are a spread of U–Al bond distances ranging from 3.09–3.34 Å. In the second U site, U is bonded in a 1-coordinate geometry to one U and twelve Al atoms. The U–U bond length is 2.59 Å. There are a spread of U–Al bond distances ranging from 3.08–3.34 Å. There are three inequivalent Al sites. In the first Al site, Al is bonded to six U and six Al atoms to form a mixture of corner, edge, and face-sharing AlU6Al6 cuboctahedra. There are a spread of Al–Al bond distances ranging from 2.65–2.94 Å. In the second Al site, Al is bonded to six U and six Al atoms to form a mixture of corner, edge, and face-sharing AlU6Al6 cuboctahedra. There are two shorter (2.70 Å) and four longer (2.80 Å) Al–Al bond lengths. In the third Al site, Al is bonded to six U and six Al atoms to form a mixture of corner, edge, and face-sharing AlU6Al6 cuboctahedra.