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DOE OSTI · 1652332

Materials Data on Na(NbS2)2 by Materials Project

Abstract

Na(NbS2)2 crystallizes in the trigonal P3m1 space group. The structure is two-dimensional and consists of one Na(NbS2)2 sheet oriented in the (0, 0, 1) direction. Na1+ is bonded in a 6-coordinate geometry to six S2- atoms. There are three shorter (2.82 Å) and three longer (2.83 Å) Na–S bond lengths. There are two inequivalent Nb+3.50+ sites. In the first Nb+3.50+ site, Nb+3.50+ is bonded to six S2- atoms to form distorted edge-sharing NbS6 pentagonal pyramids. There are three shorter (2.49 Å) and three longer (2.53 Å) Nb–S bond lengths. In the second Nb+3.50+ site, Nb+3.50+ is bonded to six S2- atoms to form distorted edge-sharing NbS6 pentagonal pyramids. There are three shorter (2.49 Å) and three longer (2.53 Å) Nb–S bond lengths. There are four inequivalent S2- sites. In the first S2- site, S2- is bonded to three equivalent Na1+ and three equivalent Nb+3.50+ atoms to form a mixture of corner, edge, and face-sharing SNa3Nb3 octahedra. In the second S2- site, S2- is bonded to three equivalent Na1+ and three equivalent Nb+3.50+ atoms to form a mixture of distorted corner, edge, and face-sharing SNa3Nb3 pentagonal pyramids. The corner-sharing octahedral tilt angles are 41°. In the third S2- site, S2- is bonded in a distorted T-shaped geometry to three equivalent Nb+3.50+ atoms. In the fourth S2- site, S2- is bonded in a distorted T-shaped geometry to three equivalent Nb+3.50+ atoms.

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2020-07-23. Materials Data on Na(NbS2)2 by Materials Project. https://doi.org/10.17188/1652332

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