Materials Data on Si(Hg2Se3)2 by Materials Project
Hg4SiSe6 is Chalcostibite-like structured and crystallizes in the monoclinic Cc space group. The structure is three-dimensional. there are four inequivalent Hg2+ sites. In the first Hg2+ site, Hg2+ is bonded in a 5-coordinate geometry to five Se2- atoms. There are a spread of Hg–Se bond distances ranging from 2.71–3.49 Å. In the second Hg2+ site, Hg2+ is bonded to four Se2- atoms to form HgSe4 tetrahedra that share corners with two equivalent SiSe4 tetrahedra and corners with five HgSe4 tetrahedra. There are a spread of Hg–Se bond distances ranging from 2.66–2.83 Å. In the third Hg2+ site, Hg2+ is bonded to four Se2- atoms to form HgSe4 tetrahedra that share corners with two equivalent SiSe4 tetrahedra and corners with five HgSe4 tetrahedra. There are a spread of Hg–Se bond distances ranging from 2.69–2.85 Å. In the fourth Hg2+ site, Hg2+ is bonded to four Se2- atoms to form distorted HgSe4 tetrahedra that share corners with two equivalent SiSe4 tetrahedra and corners with six HgSe4 tetrahedra. There are a spread of Hg–Se bond distances ranging from 2.69–2.84 Å. Si4+ is bonded to four Se2- atoms to form SiSe4 tetrahedra that share corners with six HgSe4 tetrahedra. There are a spread of Si–Se bond distances ranging from 2.28–2.31 Å. There are six inequivalent Se2- sites. In the first Se2- site, Se2- is bonded to four Hg2+ atoms to form distorted corner-sharing SeHg4 trigonal pyramids. In the second Se2- site, Se2- is bonded in a distorted trigonal non-coplanar geometry to two Hg2+ and one Si4+ atom. In the third Se2- site, Se2- is bonded in a distorted trigonal non-coplanar geometry to two Hg2+ and one Si4+ atom. In the fourth Se2- site, Se2- is bonded in a 3-coordinate geometry to three Hg2+ and one Si4+ atom. In the fifth Se2- site, Se2- is bonded to four Hg2+ atoms to form corner-sharing SeHg4 tetrahedra. In the sixth Se2- site, Se2- is bonded in a 3-coordinate geometry to two Hg2+ and one Si4+ atom.