Materials Data on NaNb(CuS2)2 by Materials Project
NaNb(CuS2)2 is Chalcostibite-derived structured and crystallizes in the orthorhombic Ama2 space group. The structure is three-dimensional. Na1+ is bonded in a 3-coordinate geometry to three S2- atoms. There are a spread of Na–S bond distances ranging from 3.41–3.45 Å. Nb5+ is bonded to four S2- atoms to form NbS4 tetrahedra that share edges with four CuS4 tetrahedra. There are a spread of Nb–S bond distances ranging from 2.30–2.34 Å. There are two inequivalent Cu1+ sites. In the first Cu1+ site, Cu1+ is bonded to four S2- atoms to form CuS4 tetrahedra that share corners with four equivalent CuS4 tetrahedra and edges with two equivalent NbS4 tetrahedra. There are two shorter (2.34 Å) and two longer (2.35 Å) Cu–S bond lengths. In the second Cu1+ site, Cu1+ is bonded to four S2- atoms to form CuS4 tetrahedra that share corners with six CuS4 tetrahedra and edges with two equivalent NbS4 tetrahedra. There are two shorter (2.32 Å) and two longer (2.35 Å) Cu–S bond lengths. There are three inequivalent S2- sites. In the first S2- site, S2- is bonded in a 5-coordinate geometry to one Na1+, one Nb5+, and three Cu1+ atoms. In the second S2- site, S2- is bonded in a 3-coordinate geometry to one Nb5+ and two Cu1+ atoms. In the third S2- site, S2- is bonded in a 4-coordinate geometry to two equivalent Na1+, one Nb5+, and one Cu1+ atom.