Materials Data on Sc(US2)3 by Materials Project

Abstract

U3ScS6 crystallizes in the orthorhombic Pnnm space group. The structure is three-dimensional. there are three inequivalent U3+ sites. In the first U3+ site, U3+ is bonded in a 8-coordinate geometry to eight S2- atoms. There are a spread of U–S bond distances ranging from 2.77–2.95 Å. In the second U3+ site, U3+ is bonded to seven S2- atoms to form distorted US7 pentagonal bipyramids that share a cornercorner with one ScS6 octahedra, edges with two equivalent ScS6 octahedra, and edges with two equivalent US7 pentagonal bipyramids. The corner-sharing octahedral tilt angles are 32°. There are a spread of U–S bond distances ranging from 2.68–2.87 Å. In the third U3+ site, U3+ is bonded in a 8-coordinate geometry to eight S2- atoms. There are a spread of U–S bond distances ranging from 2.77–3.14 Å. There are two inequivalent Sc3+ sites. In the first Sc3+ site, Sc3+ is bonded to six S2- atoms to form ScS6 octahedra that share edges with two equivalent ScS6 octahedra and edges with four equivalent US7 pentagonal bipyramids. There are two shorter (2.56 Å) and four longer (2.58 Å) Sc–S bond lengths. In the second Sc3+ site, Sc3+ is bonded to six S2- atoms to form ScS6 octahedra that share corners with two equivalent US7 pentagonal bipyramids and edges with two equivalent ScS6 octahedra. There are two shorter (2.45 Å) and four longer (2.59 Å) Sc–S bond lengths. There are six inequivalent S2- sites. In the first S2- site, S2- is bonded to three U3+ and one Sc3+ atom to form distorted SScU3 trigonal pyramids that share corners with two equivalent SScU4 square pyramids, corners with five SSc2U3 trigonal bipyramids, corners with three equivalent SScU3 trigonal pyramids, and a faceface with one SU5 trigonal bipyramid. In the second S2- site, S2- is bonded in a 5-coordinate geometry to three U3+ and two equivalent Sc3+ atoms. In the third S2- site, S2- is bonded to three U3+ and two equivalent Sc3+ atoms to form distorted SSc2U3 trigonal bipyramids that share corners with five SSc2U3 trigonal bipyramids, corners with three equivalent SScU3 trigonal pyramids, edges with four equivalent SScU4 square pyramids, and edges with three SU5 trigonal bipyramids. In the fourth S2- site, S2- is bonded to four U3+ and one Sc3+ atom to form distorted SScU4 square pyramids that share a cornercorner with one SScU4 square pyramid, corners with four equivalent SU5 trigonal bipyramids, corners with two equivalent SScU3 trigonal pyramids, edges with two equivalent SScU4 square pyramids, and edges with five SSc2U3 trigonal bipyramids. In the fifth S2- site, S2- is bonded to five U3+ atoms to form distorted SU5 trigonal bipyramids that share corners with four equivalent SScU4 square pyramids, a cornercorner with one SSc2U3 trigonal bipyramid, corners with two equivalent SScU3 trigonal pyramids, an edgeedge with one SScU4 square pyramid, edges with four SSc2U3 trigonal bipyramids, and a faceface with one SScU3 trigonal pyramid. In the sixth S2- site, S2- is bonded in a 5-coordinate geometry to five U3+ atoms.