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DOE OSTI · 1298701

Materials Data on Y2Hg2O5 by Materials Project

Abstract

Y2Hg2O5 crystallizes in the orthorhombic Pna2_1 space group. The structure is three-dimensional. there are two inequivalent Y3+ sites. In the first Y3+ site, Y3+ is bonded to six O2- atoms to form YO6 octahedra that share corners with five equivalent YO6 octahedra, corners with three HgO5 square pyramids, edges with two equivalent YO6 octahedra, and edges with four HgO5 square pyramids. The corner-sharing octahedra tilt angles range from 0–55°. There are a spread of Y–O bond distances ranging from 2.26–2.49 Å. In the second Y3+ site, Y3+ is bonded to six O2- atoms to form YO6 octahedra that share corners with five equivalent YO6 octahedra, corners with three HgO5 square pyramids, edges with two equivalent YO6 octahedra, and edges with four HgO5 square pyramids. The corner-sharing octahedra tilt angles range from 0–55°. There are a spread of Y–O bond distances ranging from 2.26–2.49 Å. There are two inequivalent Hg2+ sites. In the first Hg2+ site, Hg2+ is bonded to five O2- atoms to form distorted HgO5 square pyramids that share corners with three YO6 octahedra, corners with four HgO5 square pyramids, edges with four YO6 octahedra, and edges with two equivalent HgO5 square pyramids. The corner-sharing octahedra tilt angles range from 51–75°. There are a spread of Hg–O bond distances ranging from 2.25–2.61 Å. In the second Hg2+ site, Hg2+ is bonded to five O2- atoms to form distorted HgO5 square pyramids that share corners with three YO6 octahedra, corners with four HgO5 square pyramids, edges with four YO6 octahedra, and edges with two equivalent HgO5 square pyramids. The corner-sharing octahedra tilt angles range from 50–75°. There are a spread of Hg–O bond distances ranging from 2.24–2.60 Å. There are five inequivalent O2- sites. In the first O2- site, O2- is bonded to two equivalent Y3+ and two Hg2+ atoms to form distorted OY2Hg2 tetrahedra that share corners with two equivalent OY2Hg4 octahedra, corners with two equivalent OY2Hg2 tetrahedra, corners with six OY3Hg trigonal pyramids, edges with two equivalent OY2Hg4 octahedra, an edgeedge with one OY2Hg2 tetrahedra, and an edgeedge with one OY3Hg trigonal pyramid. The corner-sharing octahedra tilt angles range from 40–55°. In the second O2- site, O2- is bonded to three Y3+ and one Hg2+ atom to form distorted OY3Hg trigonal pyramids that share a cornercorner with one OY2Hg4 octahedra, corners with six OY2Hg2 tetrahedra, corners with six OY3Hg trigonal pyramids, edges with two equivalent OY2Hg4 octahedra, and an edgeedge with one OY2Hg2 tetrahedra. The corner-sharing octahedral tilt angles are 17°. In the third O2- site, O2- is bonded to two Y3+ and four Hg2+ atoms to form OY2Hg4 octahedra that share corners with four OY2Hg2 tetrahedra, corners with two OY3Hg trigonal pyramids, edges with two equivalent OY2Hg4 octahedra, edges with four OY2Hg2 tetrahedra, and edges with four OY3Hg trigonal pyramids. In the fourth O2- site, O2- is bonded to three Y3+ and one Hg2+ atom to form distorted OY3Hg trigonal pyramids that share a cornercorner with one OY2Hg4 octahedra, corners with six OY2Hg2 tetrahedra, corners with six OY3Hg trigonal pyramids, edges with two equivalent OY2Hg4 octahedra, and an edgeedge with one OY2Hg2 tetrahedra. The corner-sharing octahedral tilt angles are 17°. In the fifth O2- site, O2- is bonded to two equivalent Y3+ and two Hg2+ atoms to form distorted OY2Hg2 tetrahedra that share corners with two equivalent OY2Hg4 octahedra, corners with two equivalent OY2Hg2 tetrahedra, corners with six OY3Hg trigonal pyramids, edges with two equivalent OY2Hg4 octahedra, an edgeedge with one OY2Hg2 tetrahedra, and an edgeedge with one OY3Hg trigonal pyramid. The corner-sharing octahedra tilt angles range from 41–55°.

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2020-04-29. Materials Data on Y2Hg2O5 by Materials Project. https://doi.org/10.17188/1298701

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