Materials Data on Nd8Sb2S15 by Materials Project

Nd8Sb2S15 crystallizes in the tetragonal I4_1cd space group. The structure is three-dimensional. there are four inequivalent Nd3+ sites. In the first Nd3+ site, Nd3+ is bonded to seven S2- atoms to form a mixture of distorted edge, face, and corner-sharing NdS7 pentagonal bipyramids. There are a spread of Nd–S bond distances ranging from 2.75–3.09 Å. In the second Nd3+ site, Nd3+ is bonded to seven S2- atoms to form a mixture of distorted edge, face, and corner-sharing NdS7 pentagonal bipyramids. There are a spread of Nd–S bond distances ranging from 2.75–3.03 Å. In the third Nd3+ site, Nd3+ is bonded in a 8-coordinate geometry to eight S2- atoms. There are a spread of Nd–S bond distances ranging from 2.93–3.28 Å. In the fourth Nd3+ site, Nd3+ is bonded in a 8-coordinate geometry to eight S2- atoms. There are a spread of Nd–S bond distances ranging from 2.87–3.01 Å. Sb3+ is bonded in a 3-coordinate geometry to four S2- atoms. There are a spread of Sb–S bond distances ranging from 2.49–3.11 Å. There are eight inequivalent S2- sites. In the first S2- site, S2- is bonded to five Nd3+ and one Sb3+ atom to form distorted SNd5Sb octahedra that share corners with two equivalent SNd5Sb octahedra, corners with two equivalent SNd4 tetrahedra, corners with two SNd4Sb trigonal bipyramids, edges with two SNd4Sb trigonal bipyramids, and faces with two SNd4Sb trigonal bipyramids. The corner-sharing octahedral tilt angles are 52°. In the second S2- site, S2- is bonded to four Nd3+ and one Sb3+ atom to form distorted SNd4Sb trigonal bipyramids that share a cornercorner with one SNd5Sb octahedra, corners with three equivalent SNd5 trigonal bipyramids, an edgeedge with one SNd5Sb octahedra, an edgeedge with one SNd4 tetrahedra, an edgeedge with one SNd5 trigonal bipyramid, and a faceface with one SNd5Sb octahedra. The corner-sharing octahedral tilt angles are 38°. In the third S2- site, S2- is bonded in a rectangular see-saw-like geometry to three Nd3+ and one Sb3+ atom. In the fourth S2- site, S2- is bonded to four Nd3+ atoms to form distorted SNd4 tetrahedra that share corners with four equivalent SNd5Sb octahedra and edges with four SNd4Sb trigonal bipyramids. The corner-sharing octahedral tilt angles are 43°. In the fifth S2- site, S2- is bonded to five Nd3+ atoms to form SNd5 trigonal bipyramids that share a cornercorner with one SNd5Sb octahedra, corners with five SNd4Sb trigonal bipyramids, an edgeedge with one SNd5Sb octahedra, an edgeedge with one SNd4 tetrahedra, an edgeedge with one SNd4Sb trigonal bipyramid, and a faceface with one SNd5Sb octahedra. The corner-sharing octahedral tilt angles are 37°. In the sixth S2- site, S2- is bonded in a distorted rectangular see-saw-like geometry to three Nd3+ and one Sb3+ atom. In the seventh S2- site, S2- is bonded in a rectangular see-saw-like geometry to four Nd3+ atoms. In the eighth S2- site, S2- is bonded in a 4-coordinate geometry to four Nd3+ atoms.