Materials Data on K2HgS2 by Materials Project

Abstract

K2HgS2 crystallizes in the orthorhombic Pbcm space group. The structure is three-dimensional. there are two inequivalent K1+ sites. In the first K1+ site, K1+ is bonded to five S2- atoms to form distorted KS5 trigonal bipyramids that share corners with six equivalent KS6 octahedra, corners with four equivalent KS5 trigonal bipyramids, edges with four equivalent KS5 trigonal bipyramids, and faces with two equivalent KS6 octahedra. The corner-sharing octahedra tilt angles range from 34–48°. There are a spread of K–S bond distances ranging from 3.09–3.77 Å. In the second K1+ site, K1+ is bonded to six S2- atoms to form KS6 octahedra that share corners with four equivalent KS6 octahedra, corners with six equivalent KS5 trigonal bipyramids, edges with two equivalent KS6 octahedra, faces with two equivalent KS6 octahedra, and faces with two equivalent KS5 trigonal bipyramids. The corner-sharing octahedral tilt angles are 49°. There are a spread of K–S bond distances ranging from 3.24–3.43 Å. Hg2+ is bonded in a linear geometry to two S2- atoms. Both Hg–S bond lengths are 2.35 Å. There are two inequivalent S2- sites. In the first S2- site, S2- is bonded in a 7-coordinate geometry to six K1+ and one Hg2+ atom. In the second S2- site, S2- is bonded to five K1+ and one Hg2+ atom to form a mixture of distorted edge and corner-sharing SK5Hg pentagonal pyramids.