DOE OSTI2020
Hg3(AsO4)2 crystallizes in the monoclinic P2_1/c space group. The structure is three-dimensional. there are three inequivalent Hg2+ sites. In the first 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 2.16–2.59 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 2.10–2.91 Å. In the third 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 2.15–2.98 Å. There are two inequivalent As5+ sites. In the first As5+ site, As5+ is bonded in a tetrahedral geometry to four O2- atoms. There are a spread of As–O bond distances ranging from 1.70–1.75 Å. In the second As5+ site, As5+ is bonded in a tetrahedral geometry to four O2- atoms. There are a spread of As–O bond distances ranging from 1.70–1.75 Å. There are eight inequivalent O2- sites. In the first O2- site, O2- is bonded in a distorted bent 120 degrees geometry to three Hg2+ and one As5+ atom. In the second O2- site, O2- is bonded in a 1-coordinate geometry to two equivalent Hg2+ and one As5+ atom. In the third O2- site, O2- is bonded in a distorted trigonal non-coplanar geometry to two Hg2+ and one As5+ atom. In the fourth O2- site, O2- is bonded in a distorted bent 120 degrees geometry to two Hg2+ and one As5+ atom. In the fifth O2- site, O2- is bonded in a 3-coordinate geometry to two Hg2+ and one As5+ atom. In the sixth O2- site, O2- is bonded in a distorted single-bond geometry to two Hg2+ and one As5+ atom. In the seventh O2- site, O2- is bonded in a 3-coordinate geometry to two equivalent Hg2+ and one As5+ atom. In the eighth O2- site, O2- is bonded in a 3-coordinate geometry to two equivalent Hg2+ and one As5+ atom.