Materials Data on Sm4U2O11 by Materials Project
U2Sm4O11 crystallizes in the monoclinic C2 space group. The structure is three-dimensional. U5+ is bonded in a 8-coordinate geometry to seven O2- atoms. There are a spread of U–O bond distances ranging from 2.16–2.42 Å. There are two inequivalent Sm3+ sites. In the first Sm3+ site, Sm3+ is bonded in a 7-coordinate geometry to seven O2- atoms. There are a spread of Sm–O bond distances ranging from 2.30–2.46 Å. In the second Sm3+ site, Sm3+ is bonded in a 7-coordinate geometry to seven O2- atoms. There are a spread of Sm–O bond distances ranging from 2.29–2.46 Å. There are seven inequivalent O2- sites. In the first O2- site, O2- is bonded to four Sm3+ atoms to form a mixture of edge and corner-sharing OSm4 tetrahedra. In the second O2- site, O2- is bonded to one U5+ and three Sm3+ atoms to form distorted OSm3U tetrahedra that share corners with ten OSm4 tetrahedra and edges with five OSm3U tetrahedra. In the third O2- site, O2- is bonded to two equivalent U5+ and two Sm3+ atoms to form a mixture of edge and corner-sharing OSm2U2 tetrahedra. In the fourth O2- site, O2- is bonded to two equivalent U5+ and two equivalent Sm3+ atoms to form OSm2U2 tetrahedra that share corners with eight OSm3U tetrahedra and edges with six OSm2U2 tetrahedra. In the fifth O2- site, O2- is bonded in a distorted trigonal non-coplanar geometry to one U5+ and two Sm3+ atoms. In the sixth O2- site, O2- is bonded to two equivalent U5+ and two equivalent Sm3+ atoms to form OSm2U2 tetrahedra that share corners with twelve OSm4 tetrahedra and edges with four OSm3U tetrahedra. In the seventh O2- site, O2- is bonded to one U5+ and three Sm3+ atoms to form OSm3U tetrahedra that share corners with ten OSm4 tetrahedra and edges with five OSm2U2 tetrahedra.