Materials Data on Na6FeS4 by Materials Project
Na6FeS4 crystallizes in the hexagonal P6_3mc space group. The structure is three-dimensional. there are two inequivalent Na1+ sites. In the first Na1+ site, Na1+ is bonded to four S2- atoms to form distorted NaS4 tetrahedra that share corners with two equivalent FeS4 tetrahedra, corners with eight equivalent NaS4 tetrahedra, and an edgeedge with one FeS4 tetrahedra. There are a spread of Na–S bond distances ranging from 2.76–2.91 Å. In the second Na1+ site, Na1+ is bonded in a 5-coordinate geometry to six S2- atoms. There are a spread of Na–S bond distances ranging from 2.84–3.44 Å. Fe2+ is bonded to four S2- atoms to form FeS4 tetrahedra that share corners with six equivalent NaS4 tetrahedra and edges with three equivalent NaS4 tetrahedra. All Fe–S bond lengths are 2.36 Å. There are two inequivalent S2- sites. In the first S2- site, S2- is bonded in a 8-coordinate geometry to seven Na1+ and one Fe2+ atom. In the second S2- site, S2- is bonded in a 7-coordinate geometry to nine Na1+ and one Fe2+ atom.