Materials Data on Hg2Se2O7 by Materials Project
Hg2Se2O7 crystallizes in the monoclinic P2_1/c space group. The structure is three-dimensional. there are two inequivalent Hg2+ sites. In the first Hg2+ site, Hg2+ is bonded in a 7-coordinate geometry to seven O2- atoms. There are a spread of Hg–O bond distances ranging from 2.21–2.88 Å. In the second Hg2+ site, Hg2+ is bonded in a 5-coordinate geometry to five O2- atoms. There are a spread of Hg–O bond distances ranging from 2.05–2.91 Å. There are two inequivalent Se5+ sites. In the first Se5+ site, Se5+ is bonded in a trigonal non-coplanar geometry to three O2- atoms. There is two shorter (1.73 Å) and one longer (1.76 Å) Se–O bond length. In the second Se5+ site, Se5+ is bonded in a trigonal non-coplanar geometry to three O2- atoms. There are a spread of Se–O bond distances ranging from 1.72–1.77 Å. There are seven inequivalent O2- sites. In the first O2- site, O2- is bonded in a bent 120 degrees geometry to one Hg2+ and one Se5+ atom. In the second O2- site, O2- is bonded in a 1-coordinate geometry to three Hg2+ and one Se5+ atom. In the third O2- site, O2- is bonded in a single-bond geometry to one Hg2+ atom. In the fourth O2- site, O2- is bonded in a 4-coordinate geometry to three equivalent Hg2+ and one Se5+ atom. In the fifth O2- site, O2- is bonded in a 3-coordinate geometry to two Hg2+ and one Se5+ atom. In the sixth O2- site, O2- is bonded in a water-like geometry to one Hg2+ and one Se5+ atom. In the seventh O2- site, O2- is bonded in a distorted water-like geometry to one Hg2+ and one Se5+ atom.