Materials Data on Hg2Te2O7 by Materials Project

Abstract

Hg2Te2O7 crystallizes in the monoclinic C2/c space group. The structure is three-dimensional. there are four inequivalent Hg2+ sites. In the first Hg2+ site, Hg2+ is bonded in a 4-coordinate geometry to four O2- atoms. There are two shorter (2.19 Å) and two longer (2.47 Å) Hg–O bond lengths. In the second Hg2+ site, Hg2+ is bonded in a 8-coordinate geometry to six O2- atoms. There are a spread of Hg–O bond distances ranging from 2.22–2.69 Å. In the third Hg2+ site, Hg2+ is bonded in a 2-coordinate geometry to four O2- atoms. There are two shorter (2.09 Å) and two longer (2.80 Å) Hg–O bond lengths. In the fourth Hg2+ site, Hg2+ is bonded to six O2- atoms to form distorted HgO6 pentagonal pyramids that share corners with four TeO6 octahedra. The corner-sharing octahedra tilt angles range from 50–56°. There are a spread of Hg–O bond distances ranging from 2.32–2.51 Å. There are three inequivalent Te5+ sites. In the first Te5+ site, Te5+ is bonded to six O2- atoms to form TeO6 octahedra that share corners with two equivalent TeO6 octahedra and corners with two equivalent HgO6 pentagonal pyramids. The corner-sharing octahedral tilt angles are 37°. There is two shorter (1.95 Å) and four longer (1.98 Å) Te–O bond length. In the second Te5+ site, Te5+ is bonded to six O2- atoms to form TeO6 octahedra that share corners with two equivalent TeO6 octahedra and corners with two equivalent HgO6 pentagonal pyramids. The corner-sharing octahedral tilt angles are 37°. There are a spread of Te–O bond distances ranging from 1.94–2.00 Å. In the third Te5+ site, Te5+ is bonded in a 4-coordinate geometry to four O2- atoms. There are a spread of Te–O bond distances ranging from 1.93–2.17 Å. There are seven inequivalent O2- sites. In the first O2- site, O2- is bonded in a bent 150 degrees geometry to two Te5+ atoms. In the second O2- site, O2- is bonded in a 3-coordinate geometry to two Hg2+ and one Te5+ atom. In the third O2- site, O2- is bonded in a 2-coordinate geometry to one Hg2+ and two Te5+ atoms. In the fourth O2- site, O2- is bonded in a distorted trigonal planar geometry to two Hg2+ and one Te5+ atom. In the fifth O2- site, O2- is bonded in a 4-coordinate geometry to two Hg2+ and two Te5+ atoms. In the sixth O2- site, O2- is bonded in a distorted trigonal non-coplanar geometry to two Hg2+ and one Te5+ atom. In the seventh O2- site, O2- is bonded in a 2-coordinate geometry to one Hg2+ and one Te5+ atom.