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Materials Data on NbW3S8 by Materials Project

NbWS4(WS2)2 is Molybdenite-derived structured and crystallizes in the orthorhombic Pmm2 space group. The structure is two-dimensional and consists of one NbWS4 sheet oriented in the (0, 0, 1) direction and one WS2 sheet oriented in the (0, 0, 1) direction. In the NbWS4 sheet, Nb5+ is bonded to six S2- atoms to form distorted NbS6 pentagonal pyramids that share edges with two equivalent NbS6 pentagonal pyramids and edges with four equivalent WS6 pentagonal pyramids. There are four shorter (2.46 Å) and two longer (2.48 Å) Nb–S bond lengths. W+3.67+ is bonded to six S2- atoms to form distorted WS6 pentagonal pyramids that share edges with two equivalent WS6 pentagonal pyramids and edges with four equivalent NbS6 pentagonal pyramids. There are two shorter (2.42 Å) and four longer (2.43 Å) W–S bond lengths. There are two inequivalent S2- sites. In the first S2- site, S2- is bonded in a 3-coordinate geometry to two equivalent Nb5+ and one W+3.67+ atom. In the second S2- site, S2- is bonded in a 3-coordinate geometry to one Nb5+ and two equivalent W+3.67+ atoms. In the WS2 sheet, W+3.67+ is bonded to six equivalent S2- atoms to form distorted edge-sharing WS6 pentagonal pyramids. All W–S bond lengths are 2.43 Å. S2- is bonded in a 3-coordinate geometry to three equivalent W+3.67+ atoms.

36 MATERIALS SCIENCE↗

Materials Data on Nb3WS8 by Materials Project

(NbS2)3WS2 is Molybdenite-derived structured and crystallizes in the trigonal R3m space group. The structure is two-dimensional and consists of nine NbS2 sheets oriented in the (0, 0, 1) direction and three WS2 sheets oriented in the (0, 0, 1) direction. In each NbS2 sheet, Nb+4.67+ is bonded to six equivalent S2- atoms to form distorted edge-sharing NbS6 pentagonal pyramids. All Nb–S bond lengths are 2.49 Å. S2- is bonded in a 3-coordinate geometry to three equivalent Nb+4.67+ atoms. In each WS2 sheet, W2+ is bonded to six equivalent S2- atoms to form distorted edge-sharing WS6 pentagonal pyramids. All W–S bond lengths are 2.45 Å. S2- is bonded in a 3-coordinate geometry to three equivalent W2+ atoms.

36 MATERIALS SCIENCE↗