Materials Data on K2AsAuS4 by Materials Project

Abstract

K2AuAsS4 crystallizes in the monoclinic P2_1/m space group. The structure is three-dimensional. there are two inequivalent K1+ sites. In the first K1+ site, K1+ is bonded in a 9-coordinate geometry to nine S2- atoms. There are a spread of K–S bond distances ranging from 3.21–3.62 Å. In the second K1+ site, K1+ is bonded to six S2- atoms to form distorted KS6 octahedra that share corners with two equivalent KS6 octahedra, corners with two equivalent AsS4 tetrahedra, edges with two equivalent KS6 octahedra, and edges with two equivalent AsS4 tetrahedra. The corner-sharing octahedral tilt angles are 7°. There are a spread of K–S bond distances ranging from 3.25–3.52 Å. Au1+ is bonded in a linear geometry to two equivalent S2- atoms. Both Au–S bond lengths are 2.32 Å. As5+ is bonded to four S2- atoms to form AsS4 tetrahedra that share corners with two equivalent KS6 octahedra and edges with two equivalent KS6 octahedra. The corner-sharing octahedra tilt angles range from 14–66°. There are two shorter (2.16 Å) and two longer (2.24 Å) As–S bond lengths. There are three inequivalent S2- sites. In the first S2- site, S2- is bonded in a 6-coordinate geometry to five K1+ and one As5+ atom. In the second S2- site, S2- is bonded to four K1+ and one As5+ atom to form a mixture of distorted corner and edge-sharing SK4As trigonal bipyramids. In the third S2- site, S2- is bonded in a 1-coordinate geometry to three K1+, one Au1+, and one As5+ atom.