Materials Data on La3UAl8 by Materials Project

Abstract

ULa3Al8 is Hexagonal Laves-derived structured and crystallizes in the trigonal R3m space group. The structure is three-dimensional. U is bonded in a 12-coordinate geometry to four La and twelve Al atoms. There are one shorter (3.45 Å) and three longer (3.47 Å) U–La bond lengths. There are a spread of U–Al bond distances ranging from 3.30–3.33 Å. There are three inequivalent La sites. In the first La site, La is bonded in a 12-coordinate geometry to four La and twelve Al atoms. There are three shorter (3.50 Å) and one longer (3.54 Å) La–La bond lengths. There are a spread of La–Al bond distances ranging from 3.33–3.38 Å. In the second La site, La is bonded in a 12-coordinate geometry to one U, three equivalent La, and twelve Al atoms. There are a spread of La–Al bond distances ranging from 3.33–3.43 Å. In the third La site, La is bonded in a 12-coordinate geometry to three equivalent U, one La, and twelve Al atoms. There are a spread of La–Al bond distances ranging from 3.28–3.34 Å. There are four inequivalent Al sites. In the first Al site, Al is bonded to two equivalent U, four La, and six Al atoms to form a mixture of edge, face, and corner-sharing AlLa4U2Al6 cuboctahedra. There are a spread of Al–Al bond distances ranging from 2.81–2.89 Å. In the second Al site, Al is bonded to one U, five La, and six Al atoms to form a mixture of edge, face, and corner-sharing AlLa5UAl6 cuboctahedra. There are a spread of Al–Al bond distances ranging from 2.81–2.87 Å. In the third Al site, Al is bonded to three equivalent U, three equivalent La, and six Al atoms to form AlLa3U3Al6 cuboctahedra that share corners with eighteen AlLa4U2Al6 cuboctahedra, edges with six equivalent AlLa3U3Al6 cuboctahedra, and faces with eighteen AlLa4U2Al6 cuboctahedra. In the fourth Al site, Al is bonded to six La and six Al atoms to form AlLa6Al6 cuboctahedra that share corners with eighteen AlLa4U2Al6 cuboctahedra, edges with six equivalent AlLa6Al6 cuboctahedra, and faces with eighteen AlLa4U2Al6 cuboctahedra.