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DOE OSTI · 1753496

Materials Data on Ca2LaGaCu2O7 by Materials Project

Abstract

Ca2LaCu2GaO7 crystallizes in the triclinic P1 space group. The structure is three-dimensional. there are four inequivalent Ca2+ sites. In the first Ca2+ site, Ca2+ is bonded in a 7-coordinate geometry to seven O2- atoms. There are a spread of Ca–O bond distances ranging from 2.31–2.70 Å. In the second Ca2+ site, Ca2+ is bonded in a 7-coordinate geometry to seven O2- atoms. There are a spread of Ca–O bond distances ranging from 2.29–2.74 Å. In the third Ca2+ site, Ca2+ is bonded in a 7-coordinate geometry to seven O2- atoms. There are a spread of Ca–O bond distances ranging from 2.33–2.70 Å. In the fourth Ca2+ site, Ca2+ is bonded in a body-centered cubic geometry to eight O2- atoms. There are a spread of Ca–O bond distances ranging from 2.40–2.69 Å. There are two inequivalent La3+ sites. In the first La3+ site, La3+ is bonded in a 7-coordinate geometry to eight O2- atoms. There are a spread of La–O bond distances ranging from 2.41–3.03 Å. In the second La3+ site, La3+ is bonded in a body-centered cubic geometry to eight O2- atoms. There are a spread of La–O bond distances ranging from 2.46–2.62 Å. There are four inequivalent Cu2+ sites. In the first Cu2+ site, Cu2+ is bonded to five O2- atoms to form CuO5 square pyramids that share corners with four equivalent CuO5 square pyramids and a cornercorner with one GaO4 tetrahedra. There are a spread of Cu–O bond distances ranging from 1.93–2.38 Å. In the second Cu2+ site, Cu2+ is bonded to five O2- atoms to form CuO5 square pyramids that share corners with four equivalent CuO5 square pyramids and a cornercorner with one GaO4 tetrahedra. There are a spread of Cu–O bond distances ranging from 1.93–2.29 Å. In the third Cu2+ site, Cu2+ is bonded to five O2- atoms to form CuO5 square pyramids that share corners with four equivalent CuO5 square pyramids and a cornercorner with one GaO4 tetrahedra. There are a spread of Cu–O bond distances ranging from 1.93–2.30 Å. In the fourth Cu2+ site, Cu2+ is bonded to five O2- atoms to form CuO5 square pyramids that share corners with four equivalent CuO5 square pyramids and a cornercorner with one GaO4 tetrahedra. There are a spread of Cu–O bond distances ranging from 1.93–2.41 Å. There are two inequivalent Ga3+ sites. In the first Ga3+ site, Ga3+ is bonded to four O2- atoms to form GaO4 tetrahedra that share corners with two CuO5 square pyramids and corners with two equivalent GaO4 tetrahedra. There are a spread of Ga–O bond distances ranging from 1.81–1.94 Å. In the second Ga3+ site, Ga3+ is bonded to four O2- atoms to form GaO4 tetrahedra that share corners with two CuO5 square pyramids and corners with two equivalent GaO4 tetrahedra. There are a spread of Ga–O bond distances ranging from 1.81–1.96 Å. There are fourteen inequivalent O2- sites. In the first O2- site, O2- is bonded in a 4-coordinate geometry to one Ca2+, one La3+, one Cu2+, and one Ga3+ atom. In the second O2- site, O2- is bonded in a 4-coordinate geometry to two Ca2+, one Cu2+, and one Ga3+ atom. In the third O2- site, O2- is bonded in a 4-coordinate geometry to two Ca2+, one Cu2+, and one Ga3+ atom. In the fourth O2- site, O2- is bonded in a 4-coordinate geometry to one Ca2+, two equivalent La3+, one Cu2+, and one Ga3+ atom. In the fifth O2- site, O2- is bonded to two Ca2+, two La3+, and two Cu2+ atoms to form distorted OCa2La2Cu2 octahedra that share corners with eight OCa3LaCu2 octahedra, corners with two OCa2Ga2 tetrahedra, edges with three OCa2La2Cu2 octahedra, and faces with four OCa2La2Cu2 octahedra. The corner-sharing octahedra tilt angles range from 1–67°. In the sixth O2- site, O2- is bonded to three Ca2+, one La3+, and two Cu2+ atoms to form distorted OCa3LaCu2 octahedra that share corners with eight OCa2La2Cu2 octahedra, corners with two OCa2Ga2 tetrahedra, edges with three OCa3LaCu2 octahedra, and faces with four OCa3LaCu2 octahedra. The corner-sharing octahedra tilt angles range from 2–68°. In the seventh O2- site, O2- is bonded to three Ca2+, one La3+, and two Cu2+ atoms to form distorted OCa3LaCu2 octahedra that share corners with eight OCa2La2Cu2 octahedra, corners with two OCa2Ga2 tetrahedra, edges with three OCa2La2Cu2 octahedra, and faces with four OCa3LaCu2 octahedra. The corner-sharing octahedra tilt angles range from 1–68°. In the eighth O2- site, O2- is bonded to two Ca2+, two La3+, and two Cu2+ atoms to form distorted OCa2La2Cu2 octahedra that share corners with eight OCa3LaCu2 octahedra, corners with two OCa2Ga2 tetrahedra, edges with three OCa3LaCu2 octahedra, and faces with four OCa2La2Cu2 octahedra. The corner-sharing octahedra tilt angles range from 1–67°. In the ninth O2- site, O2- is bonded to two Ca2+, two La3+, and two Cu2+ atoms to form distorted OCa2La2Cu2 octahedra that share corners with eight OCa2La2Cu2 octahedra, corners with two OCa2Ga2 tetrahedra, edges with three OCa2La2Cu2 octahedra, and faces with four OCa2La2Cu2 octahedra. The corner-sharing octahedra tilt angles range from 1–68°. In the tenth O2- site, O2- is bonded to three Ca2+, one La3+, and two Cu2+ atoms to form distorted OCa3LaCu2 octahedra that share corners with eight OCa2La2Cu2 octahedra, corners with two OCa2Ga2 tetrahedra, edges with three OCa3LaCu2 octahedra, and faces with four OCa3LaCu2 octahedra. The corner-sharing octahedra tilt angles range from 1–67°. In the eleventh O2- site, O2- is bonded to three Ca2+, one La3+, and two Cu2+ atoms to form distorted OCa3LaCu2 octahedra that share corners with eight OCa3LaCu2 octahedra, corners with two OCa2Ga2 tetrahedra, edges with three OCa2La2Cu2 octahedra, and faces with four OCa3LaCu2 octahedra. The corner-sharing octahedra tilt angles range from 1–67°. In the twelfth O2- site, O2- is bonded to two Ca2+, two La3+, and two Cu2+ atoms to form distorted OCa2La2Cu2 octahedra that share corners with eight OCa3LaCu2 octahedra, corners with two OCa2Ga2 tetrahedra, edges with three OCa3LaCu2 octahedra, and faces with four OCa2La2Cu2 octahedra. The corner-sharing octahedra tilt angles range from 1–68°. In the thirteenth O2- site, O2- is bonded to two Ca2+ and two Ga3+ atoms to form distorted OCa2Ga2 tetrahedra that share corners with eight OCa2La2Cu2 octahedra and corners with two equivalent OCaLaGa2 tetrahedra. The corner-sharing octahedra tilt angles range from 19–77°. In the fourteenth O2- site, O2- is bonded to one Ca2+, one La3+, and two Ga3+ atoms to form distorted OCaLaGa2 tetrahedra that share corners with eight OCa2La2Cu2 octahedra and corners with two equivalent OCa2Ga2 tetrahedra. The corner-sharing octahedra tilt angles range from 18–77°.

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2020-05-02. Materials Data on Ca2LaGaCu2O7 by Materials Project. https://doi.org/10.17188/1753496

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