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DOE OSTI · 1738329

Materials Data on Sr4CaPr2Cu4HgO14 by Materials Project

Abstract

Sr4CaPr2Cu4HgO14 crystallizes in the tetragonal I-4m2 space group. The structure is three-dimensional. there are two inequivalent Sr2+ sites. In the first Sr2+ site, Sr2+ is bonded in a 9-coordinate geometry to nine O2- atoms. There are a spread of Sr–O bond distances ranging from 2.62–2.78 Å. In the second Sr2+ site, Sr2+ is bonded in a 9-coordinate geometry to nine O2- atoms. There are a spread of Sr–O bond distances ranging from 2.65–2.75 Å. Ca2+ is bonded in a body-centered cubic geometry to eight equivalent O2- atoms. All Ca–O bond lengths are 2.48 Å. There are two inequivalent Pr4+ sites. In the first Pr4+ site, Pr4+ is bonded in a body-centered cubic geometry to eight equivalent O2- atoms. All Pr–O bond lengths are 2.48 Å. In the second Pr4+ site, Pr4+ is bonded to six O2- atoms to form PrO6 octahedra that share corners with four equivalent PrO6 octahedra, corners with two equivalent CuO5 square pyramids, and edges with four equivalent HgO6 octahedra. The corner-sharing octahedral tilt angles are 0°. There are two shorter (2.26 Å) and four longer (2.69 Å) Pr–O bond lengths. There are two inequivalent Cu2+ sites. In the first Cu2+ site, Cu2+ is bonded to five O2- atoms to form CuO5 square pyramids that share a cornercorner with one PrO6 octahedra and corners with four equivalent CuO5 square pyramids. The corner-sharing octahedral tilt angles are 0°. There are four shorter (1.93 Å) and one longer (2.15 Å) Cu–O bond lengths. In the second Cu2+ site, Cu2+ is bonded to five O2- atoms to form CuO5 square pyramids that share a cornercorner with one HgO6 octahedra and corners with four equivalent CuO5 square pyramids. The corner-sharing octahedral tilt angles are 0°. There are four shorter (1.90 Å) and one longer (2.30 Å) Cu–O bond lengths. Hg2+ is bonded to six O2- atoms to form HgO6 octahedra that share corners with four equivalent HgO6 octahedra, corners with two equivalent CuO5 square pyramids, and edges with four equivalent PrO6 octahedra. The corner-sharing octahedral tilt angles are 0°. There are two shorter (2.15 Å) and four longer (2.69 Å) Hg–O bond lengths. There are four inequivalent O2- sites. In the first O2- site, O2- is bonded to two Sr2+, two equivalent Pr4+, and two equivalent Hg2+ atoms to form a mixture of edge and corner-sharing OSr2Pr2Hg2 octahedra. The corner-sharing octahedral tilt angles are 0°. In the second O2- site, O2- is bonded to four Sr2+, one Pr4+, and one Cu2+ atom to form distorted OSr4PrCu octahedra that share corners with five equivalent OSr4PrCu octahedra and edges with eight OSr2Pr2Hg2 octahedra. The corner-sharing octahedra tilt angles range from 0–17°. In the third O2- site, O2- is bonded to four Sr2+, one Cu2+, and one Hg2+ atom to form distorted OSr4CuHg octahedra that share corners with five equivalent OSr4CuHg octahedra and edges with eight OSr2Pr2Hg2 octahedra. The corner-sharing octahedra tilt angles range from 0–21°. In the fourth O2- site, O2- is bonded in a 6-coordinate geometry to two Sr2+, one Ca2+, one Pr4+, and two Cu2+ atoms.

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2020-05-02. Materials Data on Sr4CaPr2Cu4HgO14 by Materials Project. https://doi.org/10.17188/1738329

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