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DOE OSTI · 1300872

Materials Data on Dy2Zr2O7 by Materials Project

Abstract

Dy2Zr2O7 crystallizes in the tetragonal P4_12_12 space group. The structure is three-dimensional. Dy3+ is bonded to seven O2- atoms to form distorted DyO7 pentagonal bipyramids that share corners with three equivalent ZrO5 trigonal bipyramids, edges with five equivalent DyO7 pentagonal bipyramids, and edges with three equivalent ZrO5 trigonal bipyramids. There are a spread of Dy–O bond distances ranging from 2.21–2.56 Å. Zr4+ is bonded to five O2- atoms to form distorted ZrO5 trigonal bipyramids that share corners with three equivalent DyO7 pentagonal bipyramids, a cornercorner with one ZrO5 trigonal bipyramid, edges with three equivalent DyO7 pentagonal bipyramids, and an edgeedge with one ZrO5 trigonal bipyramid. There are a spread of Zr–O bond distances ranging from 2.01–2.32 Å. There are four inequivalent O2- sites. In the first O2- site, O2- is bonded to two equivalent Dy3+ and two equivalent Zr4+ atoms to form a mixture of distorted edge and corner-sharing ODy2Zr2 trigonal pyramids. In the second O2- site, O2- is bonded in a 4-coordinate geometry to three equivalent Dy3+ and one Zr4+ atom. In the third O2- site, O2- is bonded in a distorted trigonal planar geometry to two equivalent Dy3+ and one Zr4+ atom. In the fourth O2- site, O2- is bonded in a bent 150 degrees geometry to two equivalent Zr4+ atoms.

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2020-07-15. Materials Data on Dy2Zr2O7 by Materials Project. https://doi.org/10.17188/1300872

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36 MATERIALS SCIENCE↗