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DOE OSTI · 1268786

Materials Data on Nd6Si4S17 by Materials Project

Abstract

Nd6Si4S17 crystallizes in the triclinic P-1 space group. The structure is three-dimensional. there are six inequivalent Nd3+ sites. In the first Nd3+ site, Nd3+ is bonded to seven S2- atoms to form distorted NdS7 pentagonal bipyramids that share corners with two SiS4 tetrahedra and edges with two SiS4 tetrahedra. There are a spread of Nd–S bond distances ranging from 2.83–3.00 Å. In the second 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 2.87–3.24 Å. In the third Nd3+ site, Nd3+ is bonded in a 9-coordinate geometry to nine S2- atoms. There are a spread of Nd–S bond distances ranging from 2.88–3.27 Å. In the fourth Nd3+ site, Nd3+ is bonded in a 9-coordinate geometry to eight S2- atoms. There are a spread of Nd–S bond distances ranging from 2.78–3.37 Å. In the fifth 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 2.89–3.19 Å. In the sixth 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 2.89–3.30 Å. There are four inequivalent Si4+ sites. In the first Si4+ site, Si4+ is bonded to four S2- atoms to form SiS4 tetrahedra that share a cornercorner with one NdS7 pentagonal bipyramid and an edgeedge with one NdS7 pentagonal bipyramid. There are a spread of Si–S bond distances ranging from 2.11–2.15 Å. In the second Si4+ site, Si4+ is bonded in a tetrahedral geometry to four S2- atoms. There are a spread of Si–S bond distances ranging from 2.10–2.15 Å. In the third Si4+ site, Si4+ is bonded to four S2- atoms to form SiS4 tetrahedra that share a cornercorner with one NdS7 pentagonal bipyramid. There are a spread of Si–S bond distances ranging from 2.11–2.16 Å. In the fourth Si4+ site, Si4+ is bonded to four S2- atoms to form SiS4 tetrahedra that share an edgeedge with one NdS7 pentagonal bipyramid. There are a spread of Si–S bond distances ranging from 2.12–2.15 Å. There are seventeen inequivalent S2- sites. In the first S2- site, S2- is bonded in a 3-coordinate geometry to two Nd3+ and one Si4+ atom. In the second S2- site, S2- is bonded in a distorted rectangular see-saw-like geometry to three Nd3+ and one Si4+ atom. In the third S2- site, S2- is bonded in a 1-coordinate geometry to two Nd3+ and one Si4+ atom. In the fourth S2- site, S2- is bonded in a distorted rectangular see-saw-like geometry to three Nd3+ and one Si4+ atom. In the fifth S2- site, S2- is bonded in a 4-coordinate geometry to three Nd3+ and one Si4+ atom. In the sixth S2- site, S2- is bonded in a 4-coordinate geometry to three Nd3+ and one Si4+ atom. In the seventh S2- site, S2- is bonded to three Nd3+ and one Si4+ atom to form distorted SNd3Si trigonal pyramids that share corners with two SNd3Si trigonal pyramids and an edgeedge with one SNd4 tetrahedra. In the eighth S2- site, S2- is bonded in a 4-coordinate geometry to three Nd3+ and one Si4+ atom. In the ninth S2- site, S2- is bonded in a 3-coordinate geometry to two Nd3+ and one Si4+ atom. In the tenth S2- site, S2- is bonded in a distorted T-shaped geometry to two Nd3+ and one Si4+ atom. In the eleventh S2- site, S2- is bonded to three Nd3+ and one Si4+ atom to form distorted SNd3Si trigonal pyramids that share corners with two SNd3Si trigonal pyramids and an edgeedge with one SNd4 tetrahedra. In the twelfth S2- site, S2- is bonded in a 1-coordinate geometry to four Nd3+ and one Si4+ atom. In the thirteenth S2- site, S2- is bonded to three Nd3+ and one Si4+ atom to form distorted SNd3Si trigonal pyramids that share a cornercorner with one SNd4 tetrahedra and corners with two SNd3Si trigonal pyramids. In the fourteenth S2- site, S2- is bonded in a 4-coordinate geometry to three Nd3+ and one Si4+ atom. In the fifteenth S2- site, S2- is bonded to four Nd3+ atoms to form a mixture of distorted edge and corner-sharing SNd4 tetrahedra. In the sixteenth S2- site, S2- is bonded in a 4-coordinate geometry to three Nd3+ and one Si4+ atom. In the seventeenth S2- site, S2- is bonded in a distorted T-shaped geometry to two Nd3+ and one Si4+ atom.

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2020-04-30. Materials Data on Nd6Si4S17 by Materials Project. https://doi.org/10.17188/1268786

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