DOE OSTI2020
U2RhIn8 crystallizes in the tetragonal P4/mmm space group. The structure is three-dimensional. U is bonded to twelve In atoms to form UIn12 cuboctahedra that share corners with eight equivalent UIn12 cuboctahedra, edges with twelve InU4In8 cuboctahedra, faces with five equivalent UIn12 cuboctahedra, and faces with eight InU4In8 cuboctahedra. There are a spread of U–In bond distances ranging from 3.24–3.30 Å. Rh is bonded in a body-centered cubic geometry to eight equivalent In atoms. All Rh–In bond lengths are 2.77 Å. There are three inequivalent In sites. In the first In site, In is bonded to four equivalent U and eight In atoms to form distorted InU4In8 cuboctahedra that share corners with four equivalent InU4In8 cuboctahedra, edges with eight equivalent UIn12 cuboctahedra, edges with eight equivalent InU4In8 cuboctahedra, faces with four equivalent UIn12 cuboctahedra, and faces with twelve InU4In8 cuboctahedra. There are four shorter (3.29 Å) and four longer (3.30 Å) In–In bond lengths. In the second In site, In is bonded in a 2-coordinate geometry to two equivalent U, two equivalent Rh, and two equivalent In atoms. Both In–In bond lengths are 3.25 Å. In the third In site, In is bonded to four equivalent U and eight In atoms to form InU4In8 cuboctahedra that share corners with eight equivalent InU4In8 cuboctahedra, edges with four equivalent UIn12 cuboctahedra, edges with eight equivalent InU4In8 cuboctahedra, faces with four equivalent UIn12 cuboctahedra, and faces with nine InU4In8 cuboctahedra.