Materials Data on La2US5 by Materials Project

Abstract

ULa2S5 crystallizes in the orthorhombic Pnma space group. The structure is three-dimensional. U4+ is bonded to seven S2- atoms to form distorted edge-sharing US7 pentagonal bipyramids. There are a spread of U–S bond distances ranging from 2.68–2.90 Å. La3+ is bonded in a 8-coordinate geometry to eight S2- atoms. There are a spread of La–S bond distances ranging from 2.95–3.10 Å. There are four inequivalent S2- sites. In the first S2- site, S2- is bonded to two equivalent U4+ and two equivalent La3+ atoms to form distorted SLa2U2 trigonal pyramids that share corners with six SLa4U square pyramids, corners with two equivalent SLa4U trigonal bipyramids, corners with six equivalent SLa2U2 trigonal pyramids, edges with three SLa4U square pyramids, edges with two equivalent SLa4U trigonal bipyramids, and an edgeedge with one SLa2U2 trigonal pyramid. In the second S2- site, S2- is bonded to one U4+ and four equivalent La3+ atoms to form distorted SLa4U trigonal bipyramids that share corners with six SLa4U square pyramids, corners with four equivalent SLa4U trigonal bipyramids, corners with four equivalent SLa2U2 trigonal pyramids, edges with six SLa4U square pyramids, and edges with four equivalent SLa2U2 trigonal pyramids. In the third S2- site, S2- is bonded to one U4+ and four equivalent La3+ atoms to form SLa4U square pyramids that share corners with four equivalent SLa4U square pyramids, corners with five equivalent SLa4U trigonal bipyramids, corners with eight equivalent SLa2U2 trigonal pyramids, edges with three SLa4U square pyramids, edges with two equivalent SLa4U trigonal bipyramids, edges with two equivalent SLa2U2 trigonal pyramids, and a faceface with one SLa4U square pyramid. In the fourth S2- site, S2- is bonded to one U4+ and four equivalent La3+ atoms to form distorted SLa4U square pyramids that share corners with eight SLa4U square pyramids, a cornercorner with one SLa4U trigonal bipyramid, corners with four equivalent SLa2U2 trigonal pyramids, an edgeedge with one SLa4U square pyramid, edges with four equivalent SLa4U trigonal bipyramids, edges with four equivalent SLa2U2 trigonal pyramids, and a faceface with one SLa4U square pyramid.