DOE OSTI2020
Nd4(LuS2)11 crystallizes in the monoclinic C2/m space group. The structure is three-dimensional. there are six inequivalent Lu3+ sites. In the first Lu3+ site, Lu3+ is bonded to seven S2- atoms to form distorted LuS7 pentagonal bipyramids that share corners with three LuS6 octahedra, edges with two equivalent LuS6 octahedra, and edges with four equivalent LuS7 pentagonal bipyramids. The corner-sharing octahedra tilt angles range from 39–50°. There are a spread of Lu–S bond distances ranging from 2.66–2.85 Å. In the second Lu3+ site, Lu3+ is bonded to six S2- atoms to form a mixture of edge and corner-sharing LuS6 octahedra. The corner-sharing octahedra tilt angles range from 48–59°. There are a spread of Lu–S bond distances ranging from 2.61–2.74 Å. In the third Lu3+ site, Lu3+ is bonded to six S2- atoms to form LuS6 octahedra that share corners with three equivalent LuS6 octahedra, corners with two equivalent LuS7 pentagonal bipyramids, and edges with four LuS6 octahedra. The corner-sharing octahedra tilt angles range from 50–63°. There are a spread of Lu–S bond distances ranging from 2.63–2.75 Å. In the fourth Lu3+ site, Lu3+ is bonded to six S2- atoms to form LuS6 octahedra that share corners with three equivalent LuS6 octahedra, a cornercorner with one LuS7 pentagonal bipyramid, edges with four equivalent LuS6 octahedra, and edges with two equivalent LuS7 pentagonal bipyramids. The corner-sharing octahedra tilt angles range from 50–63°. There are a spread of Lu–S bond distances ranging from 2.63–2.74 Å. In the fifth Lu3+ site, Lu3+ is bonded to six S2- atoms to form a mixture of edge and corner-sharing LuS6 octahedra. The corner-sharing octahedra tilt angles range from 48–59°. There are a spread of Lu–S bond distances ranging from 2.62–2.73 Å. In the sixth Lu3+ site, Lu3+ is bonded to six S2- atoms to form a mixture of edge and corner-sharing LuS6 octahedra. The corner-sharing octahedral tilt angles are 55°. There are four shorter (2.69 Å) and two longer (2.71 Å) Lu–S bond lengths. There are two inequivalent Nd+2.75+ sites. In the first Nd+2.75+ site, Nd+2.75+ is bonded in a 8-coordinate geometry to eight S2- atoms. There are a spread of Nd–S bond distances ranging from 2.91–3.03 Å. In the second Nd+2.75+ site, Nd+2.75+ is bonded in a 7-coordinate geometry to eight S2- atoms. There are a spread of Nd–S bond distances ranging from 2.90–3.41 Å. There are eleven inequivalent S2- sites. In the first S2- site, S2- is bonded to three Lu3+ and two equivalent Nd+2.75+ atoms to form distorted SNd2Lu3 trigonal bipyramids that share corners with two equivalent SNd2Lu3 square pyramids, corners with two equivalent SNd3Lu2 trigonal bipyramids, corners with two SNdLu3 trigonal pyramids, an edgeedge with one SNd2Lu3 square pyramid, edges with five SNd2Lu3 trigonal bipyramids, and edges with two equivalent SLu4 trigonal pyramids. In the second S2- site, S2- is bonded in a rectangular see-saw-like geometry to four Lu3+ atoms. In the third S2- site, S2- is bonded in a 4-coordinate geometry to three Lu3+ and one Nd+2.75+ atom. In the fourth S2- site, S2- is bonded to three Lu3+ and two equivalent Nd+2.75+ atoms to form distorted SNd2Lu3 square pyramids that share corners with six SNd2Lu3 trigonal bipyramids, corners with two equivalent SNdLu3 trigonal pyramids, edges with four SNd2Lu3 square pyramids, edges with two SNd2Lu3 trigonal bipyramids, and an edgeedge with one SNdLu3 trigonal pyramid. In the fifth S2- site, S2- is bonded to three Lu3+ and two equivalent Nd+2.75+ atoms to form distorted SNd2Lu3 square pyramids that share corners with two equivalent SNd2Lu3 square pyramids, corners with four SNd3Lu2 trigonal bipyramids, edges with five SNd2Lu3 square pyramids, an edgeedge with one SNd3Lu2 trigonal bipyramid, and edges with two equivalent SNdLu3 trigonal pyramids. In the sixth S2- site, S2- is bonded to three Lu3+ and two equivalent Nd+2.75+ atoms to form distorted SNd2Lu3 square pyramids that share corners with four SNd2Lu3 square pyramids, corners with two equivalent SNd3Lu2 trigonal bipyramids, corners with two equivalent SNdLu3 trigonal pyramids, edges with four SNd2Lu3 square pyramids, and edges with three SNd3Lu2 trigonal bipyramids. In the seventh S2- site, S2- is bonded to two equivalent Lu3+ and three Nd+2.75+ atoms to form distorted SNd3Lu2 trigonal bipyramids that share corners with six SNd2Lu3 square pyramids, corners with four equivalent SLu4 trigonal pyramids, edges with two SNd2Lu3 square pyramids, edges with six SNd2Lu3 trigonal bipyramids, and edges with three SNdLu3 trigonal pyramids. In the eighth S2- site, S2- is bonded to three Lu3+ and one Nd+2.75+ atom to form distorted SNdLu3 trigonal pyramids that share corners with four SNd2Lu3 square pyramids, corners with two SNd2Lu3 trigonal bipyramids, corners with five SNdLu3 trigonal pyramids, edges with three SNd2Lu3 square pyramids, and edges with two equivalent SNd3Lu2 trigonal bipyramids. In the ninth S2- site, S2- is bonded in a rectangular see-saw-like geometry to four Lu3+ atoms. In the tenth S2- site, S2- is bonded to four Lu3+ atoms to form distorted SLu4 trigonal pyramids that share corners with five SNd2Lu3 trigonal bipyramids, corners with five SNdLu3 trigonal pyramids, edges with three SNd2Lu3 trigonal bipyramids, and edges with two equivalent SLu4 trigonal pyramids. In the eleventh S2- site, S2- is bonded to two equivalent Lu3+ and three Nd+2.75+ atoms to form distorted SNd3Lu2 trigonal bipyramids that share corners with four SNd2Lu3 square pyramids, corners with two equivalent SNd2Lu3 trigonal bipyramids, a cornercorner with one SNdLu3 trigonal pyramid, edges with three SNd2Lu3 square pyramids, and edges with five SNd2Lu3 trigonal bipyramids.