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DOE OSTI · 1699205

Materials Data on Sr4CaYGa2(Cu2O7)2 by Materials Project

Abstract

Sr4CaYGa2(Cu2O7)2 crystallizes in the triclinic P1 space group. The structure is three-dimensional. there are four inequivalent Sr2+ sites. In the first Sr2+ site, Sr2+ is bonded in a 5-coordinate geometry to five O2- atoms. There are a spread of Sr–O bond distances ranging from 2.38–2.63 Å. In the second Sr2+ site, Sr2+ is bonded in a 7-coordinate geometry to seven O2- atoms. There are a spread of Sr–O bond distances ranging from 2.46–3.06 Å. In the third Sr2+ site, Sr2+ is bonded in a 7-coordinate geometry to seven O2- atoms. There are a spread of Sr–O bond distances ranging from 2.32–2.95 Å. In the fourth Sr2+ site, Sr2+ is bonded in a 7-coordinate geometry to seven O2- atoms. There are a spread of Sr–O bond distances ranging from 2.42–3.03 Å. Ca2+ is bonded in a 6-coordinate geometry to six O2- atoms. There are a spread of Ca–O bond distances ranging from 2.31–2.96 Å. Y3+ is bonded in a 7-coordinate geometry to seven O2- atoms. There are a spread of Y–O bond distances ranging from 2.16–2.75 Å. There are four inequivalent Cu+2.25+ sites. In the first Cu+2.25+ site, Cu+2.25+ is bonded in a linear geometry to two O2- atoms. There is one shorter (1.81 Å) and one longer (1.88 Å) Cu–O bond length. In the second Cu+2.25+ site, Cu+2.25+ is bonded in a distorted T-shaped geometry to three O2- atoms. There are a spread of Cu–O bond distances ranging from 1.81–1.91 Å. In the third Cu+2.25+ site, Cu+2.25+ is bonded in a T-shaped geometry to three O2- atoms. There are a spread of Cu–O bond distances ranging from 1.82–2.00 Å. In the fourth Cu+2.25+ site, Cu+2.25+ is bonded in a distorted trigonal planar geometry to three O2- atoms. There is one shorter (1.87 Å) and two longer (1.89 Å) Cu–O bond length. There are two inequivalent Ga3+ sites. In the first Ga3+ site, Ga3+ is bonded in a distorted tetrahedral geometry to four O2- atoms. There are a spread of Ga–O bond distances ranging from 1.81–1.96 Å. In the second Ga3+ site, Ga3+ is bonded in a trigonal non-coplanar geometry to three O2- atoms. There are a spread of Ga–O bond distances ranging from 1.80–1.82 Å. There are fourteen inequivalent O2- sites. In the first O2- site, O2- is bonded in a 4-coordinate geometry to two Sr2+, one Ca2+, and two Cu+2.25+ atoms. In the second O2- site, O2- is bonded in a distorted see-saw-like geometry to two Sr2+, one Ca2+, and one Cu+2.25+ atom. In the third O2- site, O2- is bonded to two Sr2+, one Cu+2.25+, and one Ga3+ atom to form distorted OSr2GaCu tetrahedra that share a cornercorner with one OSr2GaCu tetrahedra and a cornercorner with one OSr2YCu trigonal pyramid. In the fourth O2- site, O2- is bonded in a 5-coordinate geometry to two Sr2+, one Y3+, one Cu+2.25+, and one Ga3+ atom. In the fifth O2- site, O2- is bonded to two Sr2+, one Cu+2.25+, and one Ga3+ atom to form distorted OSr2GaCu tetrahedra that share a cornercorner with one OSr2GaCu tetrahedra and an edgeedge with one OSr2YCu trigonal pyramid. In the sixth O2- site, O2- is bonded in a distorted bent 120 degrees geometry to one Sr2+, one Y3+, and two Ga3+ atoms. In the seventh O2- site, O2- is bonded to two Sr2+, one Y3+, and one Cu+2.25+ atom to form a mixture of distorted edge and corner-sharing OSr2YCu trigonal pyramids. In the eighth O2- site, O2- is bonded in a distorted T-shaped geometry to one Ca2+ and two Cu+2.25+ atoms. In the ninth O2- site, O2- is bonded in a 3-coordinate geometry to one Sr2+, one Y3+, and one Ga3+ atom. In the tenth O2- site, O2- is bonded in a distorted see-saw-like geometry to one Sr2+, one Ca2+, one Y3+, and one Ga3+ atom. In the eleventh O2- site, O2- is bonded in a 4-coordinate geometry to two Sr2+, one Y3+, and one O2- atom. The O–O bond length is 1.51 Å. In the twelfth O2- site, O2- is bonded in a 4-coordinate geometry to three Sr2+, one Ca2+, and one Cu+2.25+ atom. In the thirteenth O2- site, O2- is bonded in a 5-coordinate geometry to three Sr2+, one Y3+, and one O2- atom. In the fourteenth O2- site, O2- is bonded in a 4-coordinate geometry to three Sr2+, one Ca2+, and one Cu+2.25+ atom.

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2020-04-30. Materials Data on Sr4CaYGa2(Cu2O7)2 by Materials Project. https://doi.org/10.17188/1699205

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