Materials Data on La2UAs3 by Materials Project
ULa2As3 is Caswellsilverite-like structured and crystallizes in the orthorhombic Immm space group. The structure is three-dimensional. U3+ is bonded to six As3- atoms to form UAs6 octahedra that share corners with two equivalent UAs6 octahedra, corners with four equivalent LaAs6 octahedra, edges with two equivalent UAs6 octahedra, and edges with ten equivalent LaAs6 octahedra. The corner-sharing octahedra tilt angles range from 0–4°. There are four shorter (2.92 Å) and two longer (3.03 Å) U–As bond lengths. La3+ is bonded to six As3- atoms to form LaAs6 octahedra that share corners with two equivalent UAs6 octahedra, corners with four equivalent LaAs6 octahedra, edges with five equivalent UAs6 octahedra, and edges with seven equivalent LaAs6 octahedra. The corner-sharing octahedra tilt angles range from 0–7°. There are a spread of La–As bond distances ranging from 3.03–3.12 Å. There are two inequivalent As3- sites. In the first As3- site, As3- is bonded to two equivalent U3+ and four equivalent La3+ atoms to form a mixture of corner and edge-sharing AsLa4U2 octahedra. The corner-sharing octahedra tilt angles range from 0–1°. In the second As3- site, As3- is bonded to two equivalent U3+ and four equivalent La3+ atoms to form a mixture of corner and edge-sharing AsLa4U2 octahedra. The corner-sharing octahedra tilt angles range from 0–7°.