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DOE OSTI · 1757284

Materials Data on Na6Cd7S10 by Materials Project

Abstract

Na6Cd7S10 crystallizes in the monoclinic Cm space group. The structure is three-dimensional. there are six inequivalent Na1+ sites. In the first Na1+ site, Na1+ is bonded to six S2- atoms to form NaS6 octahedra that share corners with six CdS4 tetrahedra, corners with two equivalent NaS5 trigonal bipyramids, a cornercorner with one CdS4 trigonal pyramid, edges with four NaS6 octahedra, edges with four CdS4 tetrahedra, and edges with two equivalent NaS5 trigonal bipyramids. There are a spread of Na–S bond distances ranging from 2.89–3.26 Å. In the second Na1+ site, Na1+ is bonded to six S2- atoms to form NaS6 octahedra that share corners with four CdS4 tetrahedra, corners with two equivalent NaS5 trigonal bipyramids, a cornercorner with one CdS4 trigonal pyramid, edges with four NaS6 octahedra, edges with two equivalent NaS5 square pyramids, and edges with six CdS4 tetrahedra. There are a spread of Na–S bond distances ranging from 2.80–3.16 Å. In the third Na1+ site, Na1+ is bonded to five S2- atoms to form distorted NaS5 trigonal bipyramids that share corners with five CdS4 tetrahedra, corners with three NaS5 trigonal bipyramids, edges with two equivalent NaS6 octahedra, edges with two equivalent CdS4 tetrahedra, edges with three NaS5 trigonal bipyramids, and edges with two equivalent CdS4 trigonal pyramids. There are a spread of Na–S bond distances ranging from 2.75–3.05 Å. In the fourth Na1+ site, Na1+ is bonded to five S2- atoms to form NaS5 square pyramids that share corners with five CdS4 tetrahedra, corners with three NaS5 trigonal bipyramids, edges with two equivalent NaS6 octahedra, edges with two equivalent NaS5 square pyramids, edges with three CdS4 tetrahedra, an edgeedge with one NaS5 trigonal bipyramid, and edges with two equivalent CdS4 trigonal pyramids. There are a spread of Na–S bond distances ranging from 2.78–2.91 Å. In the fifth Na1+ site, Na1+ is bonded to five S2- atoms to form NaS5 trigonal bipyramids that share corners with two equivalent NaS6 octahedra, a cornercorner with one NaS5 square pyramid, corners with three CdS4 tetrahedra, corners with four NaS5 trigonal bipyramids, corners with two equivalent CdS4 trigonal pyramids, edges with three CdS4 tetrahedra, edges with two NaS5 trigonal bipyramids, and edges with two equivalent CdS4 trigonal pyramids. The corner-sharing octahedral tilt angles are 48°. There are a spread of Na–S bond distances ranging from 2.81–3.26 Å. In the sixth Na1+ site, Na1+ is bonded to five S2- atoms to form distorted NaS5 trigonal bipyramids that share corners with two equivalent NaS6 octahedra, corners with two equivalent NaS5 square pyramids, corners with three CdS4 tetrahedra, corners with three NaS5 trigonal bipyramids, corners with two equivalent CdS4 trigonal pyramids, an edgeedge with one NaS5 square pyramid, edges with three CdS4 tetrahedra, an edgeedge with one NaS5 trigonal bipyramid, and edges with two equivalent CdS4 trigonal pyramids. The corner-sharing octahedral tilt angles are 45°. There are a spread of Na–S bond distances ranging from 2.73–3.34 Å. There are seven inequivalent Cd2+ sites. In the first Cd2+ site, Cd2+ is bonded to four S2- atoms to form CdS4 tetrahedra that share corners with two equivalent NaS6 octahedra, corners with two equivalent NaS5 square pyramids, corners with four CdS4 tetrahedra, corners with two equivalent NaS5 trigonal bipyramids, corners with two CdS4 trigonal pyramids, an edgeedge with one NaS6 octahedra, an edgeedge with one CdS4 tetrahedra, and edges with four NaS5 trigonal bipyramids. The corner-sharing octahedral tilt angles are 28°. There are a spread of Cd–S bond distances ranging from 2.59–2.62 Å. In the second Cd2+ site, Cd2+ is bonded to four S2- atoms to form CdS4 tetrahedra that share corners with two equivalent NaS6 octahedra, corners with four CdS4 tetrahedra, corners with four NaS5 trigonal bipyramids, corners with two CdS4 trigonal pyramids, an edgeedge with one NaS6 octahedra, edges with two equivalent NaS5 square pyramids, an edgeedge with one CdS4 tetrahedra, and edges with two equivalent NaS5 trigonal bipyramids. The corner-sharing octahedral tilt angles are 25°. There are a spread of Cd–S bond distances ranging from 2.57–2.64 Å. In the third Cd2+ site, Cd2+ is bonded to four S2- atoms to form CdS4 tetrahedra that share corners with two equivalent NaS6 octahedra, a cornercorner with one NaS5 square pyramid, corners with four CdS4 tetrahedra, a cornercorner with one NaS5 trigonal bipyramid, corners with two equivalent CdS4 trigonal pyramids, edges with three NaS6 octahedra, and an edgeedge with one NaS5 trigonal bipyramid. The corner-sharing octahedral tilt angles are 10°. There are a spread of Cd–S bond distances ranging from 2.53–2.65 Å. In the fourth Cd2+ site, Cd2+ is bonded to four S2- atoms to form CdS4 tetrahedra that share corners with two equivalent NaS6 octahedra, corners with six CdS4 tetrahedra, corners with two NaS5 trigonal bipyramids, corners with two equivalent CdS4 trigonal pyramids, edges with three NaS6 octahedra, and an edgeedge with one NaS5 trigonal bipyramid. The corner-sharing octahedral tilt angles are 19°. There are three shorter (2.59 Å) and one longer (2.61 Å) Cd–S bond lengths. In the fifth Cd2+ site, Cd2+ is bonded to four S2- atoms to form CdS4 tetrahedra that share corners with two equivalent NaS6 octahedra, corners with two equivalent NaS5 square pyramids, corners with four CdS4 tetrahedra, corners with two equivalent NaS5 trigonal bipyramids, corners with three CdS4 trigonal pyramids, edges with two equivalent NaS6 octahedra, and an edgeedge with one NaS5 square pyramid. The corner-sharing octahedra tilt angles range from 16–56°. There are a spread of Cd–S bond distances ranging from 2.48–2.67 Å. In the sixth Cd2+ site, Cd2+ is bonded to four S2- atoms to form CdS4 trigonal pyramids that share a cornercorner with one NaS6 octahedra, corners with five CdS4 tetrahedra, corners with two equivalent NaS5 trigonal bipyramids, corners with two equivalent CdS4 trigonal pyramids, and edges with four NaS5 trigonal bipyramids. The corner-sharing octahedral tilt angles are 37°. There are a spread of Cd–S bond distances ranging from 2.48–2.88 Å. In the seventh Cd2+ site, Cd2+ is bonded to four S2- atoms to form CdS4 trigonal pyramids that share a cornercorner with one NaS6 octahedra, corners with six CdS4 tetrahedra, corners with two equivalent NaS5 trigonal bipyramids, corners with two equivalent CdS4 trigonal pyramids, edges with two equivalent NaS5 square pyramids, and edges with two equivalent NaS5 trigonal bipyramids. The corner-sharing octahedral tilt angles are 35°. There are three shorter (2.53 Å) and one longer (3.02 Å) Cd–S bond lengths. There are ten inequivalent S2- sites. In the first S2- site, S2- is bonded to four Na1+ and three Cd2+ atoms to form distorted SNa4Cd3 pentagonal bipyramids that share corners with four SNa2Cd3 trigonal bipyramids, edges with two equivalent SNa4Cd3 pentagonal bipyramids, edges with two equivalent SNa2Cd3 trigonal bipyramids, and a faceface with one SNa3Cd2 trigonal bipyramid. In the second S2- site, S2- is bonded in a 7-coordinate geometry to four Na1+ and three Cd2+ atoms. In the third S2- site, S2- is bonded in a 7-coordinate geometry to four Na1+ and three Cd2+ atoms. In the fourth S2- site, S2- is bonded in a 7-coordinate geometry to four Na1+ and three Cd2+ atoms. In the fifth S2- site, S2- is bonded to three Na1+ and two Cd2+ atoms to form distorted SNa3Cd2 trigonal bipyramids that share corners with four SNa3Cd3 octahedra, corners with two equivalent SNa4Cd3 pentagonal bipyramids, corners with two equivalent SNa3Cd2 square pyramids, corners with four SNa2Cd3 trigonal bipyramids, and a faceface with one SNa4Cd3 pentagonal bipyramid. The corner-sharing octahedra tilt angles range from 8–64°. In the sixth S2- site, S2- is bonded to three Na1+ and three Cd2+ atoms to form SNa3Cd3 octahedra that share a cornercorner with one SNa3Cd2 square pyramid, corners with four SNa2Cd3 trigonal bipyramids, and edges with four SNa3Cd3 octahedra. In the seventh S2- site, S2- is bonded to three Na1+ and two equivalent Cd2+ atoms to form SNa3Cd2 square pyramids that share a cornercorner with one SNa3Cd3 octahedra, corners with four SNa2Cd3 trigonal bipyramids, edges with two equivalent SNa3Cd3 octahedra, and edges with two equivalent SNa3Cd2 square pyramids. The corner-sharing octahedral tilt angles are 1°. In the eighth S2- site, S2- is bonded to three Na1+ and three Cd2+ atoms to form distorted SNa3Cd3 octahedra that share corners with four SNa2Cd3 trigonal bipyramids, edges with four SNa3Cd3 octahedra, and edges with two equivalent SNa3Cd2 square pyramids. In the ninth S2- site, S2- is bonded to two Na1+ and three Cd2+ atoms to form SNa2Cd3 trigonal bipyramids that share corners with two equivalent SNa3Cd3 octahedra, corners with two equivalent SNa4Cd3 pentagonal bipyramids, corners with two equivalent SNa3Cd2 square pyramids, corners with two equivalent SNa2Cd3 trigonal bipyramids, and an edgeedge with one SNa2Cd3 trigonal bipyramid. The corner-sharing octahedral tilt angles are 57°. In the tenth S2- site, S2- is bonded to two Na1+ and three Cd2+ atoms to form SNa2Cd3 trigonal bipyramids that share corners with two equivalent SNa3Cd3 octahedra, corners with four SNa2Cd3 trigonal bipyramids, edges with two equivalent SNa4Cd3 pentagonal bipyramids, and an edgeedge with one SNa2Cd3 trigonal bipyramid. The corner-sharing octahedral tilt angles are 68°.

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2020-09-03. Materials Data on Na6Cd7S10 by Materials Project. https://doi.org/10.17188/1757284

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