Materials Data on Nd10US16 by Materials Project

Abstract

UNd10S16 crystallizes in the tetragonal P-4 space group. The structure is three-dimensional. U3+ is bonded to eight S2- atoms to form distorted US8 hexagonal bipyramids that share corners with four equivalent NdS8 hexagonal bipyramids, edges with four equivalent NdS8 hexagonal bipyramids, and faces with four equivalent NdS8 hexagonal bipyramids. There are four shorter (2.83 Å) and four longer (3.01 Å) U–S bond lengths. There are three inequivalent Nd+2.90+ sites. In the first Nd+2.90+ site, Nd+2.90+ is bonded in a 8-coordinate geometry to eight S2- atoms. There are a spread of Nd–S bond distances ranging from 2.83–3.18 Å. In the second Nd+2.90+ site, Nd+2.90+ is bonded to eight S2- atoms to form distorted NdS8 hexagonal bipyramids that share corners with four equivalent NdS8 hexagonal bipyramids, edges with two equivalent US8 hexagonal bipyramids, and faces with four equivalent NdS8 hexagonal bipyramids. There are a spread of Nd–S bond distances ranging from 2.85–3.05 Å. In the third Nd+2.90+ site, Nd+2.90+ is bonded to eight S2- atoms to form distorted NdS8 hexagonal bipyramids that share a cornercorner with one US8 hexagonal bipyramid, corners with four NdS8 hexagonal bipyramids, edges with two equivalent NdS8 hexagonal bipyramids, a faceface with one US8 hexagonal bipyramid, and faces with four NdS8 hexagonal bipyramids. There are a spread of Nd–S bond distances ranging from 2.86–3.14 Å. There are four inequivalent S2- sites. In the first S2- site, S2- is bonded to five Nd+2.90+ atoms to form distorted SNd5 trigonal bipyramids that share corners with four equivalent SNd5U octahedra, corners with four equivalent SNd5 square pyramids, a cornercorner with one SNd5 trigonal bipyramid, edges with two equivalent SNd5U octahedra, edges with two equivalent SNd5 square pyramids, and edges with three equivalent SNd5 trigonal bipyramids. The corner-sharing octahedra tilt angles range from 35–54°. In the second S2- site, S2- is bonded to five Nd+2.90+ atoms to form distorted SNd5 square pyramids that share corners with four equivalent SNd5U octahedra, corners with four equivalent SNd5 square pyramids, corners with four equivalent SNd5 trigonal bipyramids, an edgeedge with one SNd5U octahedra, edges with two equivalent SNd5 trigonal bipyramids, faces with two equivalent SNd5U octahedra, and a faceface with one SNd5 square pyramid. The corner-sharing octahedra tilt angles range from 13–53°. In the third S2- site, S2- is bonded in a 6-coordinate geometry to one U3+ and five Nd+2.90+ atoms. In the fourth S2- site, S2- is bonded to one U3+ and five Nd+2.90+ atoms to form distorted SNd5U octahedra that share corners with three equivalent SNd5U octahedra, corners with four equivalent SNd5 square pyramids, corners with four equivalent SNd5 trigonal bipyramids, edges with two equivalent SNd5U octahedra, an edgeedge with one SNd5 square pyramid, edges with two equivalent SNd5 trigonal bipyramids, a faceface with one SNd5U octahedra, and faces with two equivalent SNd5 square pyramids. The corner-sharing octahedra tilt angles range from 17–45°.