Materials Data on TlHgAsS3 by Materials Project
HgTlAsS3 crystallizes in the orthorhombic Cmce space group. The structure is three-dimensional. Hg2+ is bonded to four S2- atoms to form distorted corner-sharing HgS4 tetrahedra. There are two shorter (2.53 Å) and two longer (2.72 Å) Hg–S bond lengths. Tl1+ is bonded in a 7-coordinate geometry to seven S2- atoms. There are a spread of Tl–S bond distances ranging from 3.15–3.68 Å. As3+ is bonded in a trigonal non-coplanar geometry to three S2- atoms. There are one shorter (2.25 Å) and two longer (2.29 Å) As–S bond lengths. There are two inequivalent S2- sites. In the first S2- site, S2- is bonded in a 5-coordinate geometry to one Hg2+, three equivalent Tl1+, and one As3+ atom. In the second S2- site, S2- is bonded in a 3-coordinate geometry to two equivalent Hg2+, one Tl1+, and one As3+ atom.