Materials Data on U2Hg5(AsO9)2 by Materials Project

Abstract

U2Hg5(AsO9)2 crystallizes in the triclinic P-1 space group. The structure is three-dimensional. U is bonded to seven O atoms to form distorted UO7 pentagonal bipyramids that share corners with three equivalent AsO4 tetrahedra and an edgeedge with one UO7 pentagonal bipyramid. There are a spread of U–O bond distances ranging from 1.83–2.40 Å. There are three inequivalent Hg sites. In the first Hg site, Hg is bonded in a linear geometry to two equivalent O atoms. Both Hg–O bond lengths are 2.00 Å. In the second Hg site, Hg is bonded in a distorted linear geometry to two O atoms. There are one shorter (2.04 Å) and one longer (2.05 Å) Hg–O bond lengths. In the third Hg site, Hg is bonded in a 4-coordinate geometry to four O atoms. There are a spread of Hg–O bond distances ranging from 2.10–2.66 Å. As is bonded to four O atoms to form AsO4 tetrahedra that share corners with three equivalent UO7 pentagonal bipyramids. There are a spread of As–O bond distances ranging from 1.71–1.76 Å. There are nine inequivalent O sites. In the first O site, O is bonded in a bent 150 degrees geometry to one U and one As atom. In the second O site, O is bonded in a distorted bent 150 degrees geometry to one U and one As atom. In the third O site, O is bonded in a 1-coordinate geometry to one U, one Hg, and one As atom. In the fourth O site, O is bonded in a bent 120 degrees geometry to one Hg and one As atom. In the fifth O site, O is bonded in a 2-coordinate geometry to two Hg atoms. In the sixth O site, O is bonded in a bent 120 degrees geometry to two Hg atoms. In the seventh O site, O is bonded in a trigonal planar geometry to two equivalent U and one Hg atom. In the eighth O site, O is bonded in a single-bond geometry to one U atom. In the ninth O site, O is bonded in a single-bond geometry to one U atom.