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DOE OSTI · 1290798

Materials Data on La12Cu6O25 by Materials Project

Abstract

La12Cu6O25 crystallizes in the monoclinic C2 space group. The structure is three-dimensional. there are six inequivalent La3+ sites. In the first La3+ site, La3+ is bonded in a 9-coordinate geometry to nine O2- atoms. There are a spread of La–O bond distances ranging from 2.35–2.85 Å. In the second La3+ site, La3+ is bonded in a 9-coordinate geometry to nine O2- atoms. There are a spread of La–O bond distances ranging from 2.33–2.80 Å. In the third La3+ site, La3+ is bonded in a 8-coordinate geometry to eight O2- atoms. There are a spread of La–O bond distances ranging from 2.32–2.77 Å. In the fourth La3+ site, La3+ is bonded in a 9-coordinate geometry to nine O2- atoms. There are a spread of La–O bond distances ranging from 2.36–2.78 Å. In the fifth La3+ site, La3+ is bonded in a 9-coordinate geometry to nine O2- atoms. There are a spread of La–O bond distances ranging from 2.38–2.80 Å. In the sixth La3+ site, La3+ is bonded in a 10-coordinate geometry to eight O2- atoms. There are a spread of La–O bond distances ranging from 2.35–2.81 Å. There are three inequivalent Cu+2.33+ sites. In the first Cu+2.33+ site, Cu+2.33+ is bonded to six O2- atoms to form corner-sharing CuO6 octahedra. The corner-sharing octahedra tilt angles range from 3–5°. There are a spread of Cu–O bond distances ranging from 1.92–2.33 Å. In the second Cu+2.33+ site, Cu+2.33+ is bonded to six O2- atoms to form corner-sharing CuO6 octahedra. The corner-sharing octahedra tilt angles range from 3–17°. There are a spread of Cu–O bond distances ranging from 1.91–2.44 Å. In the third Cu+2.33+ site, Cu+2.33+ is bonded to six O2- atoms to form corner-sharing CuO6 octahedra. The corner-sharing octahedra tilt angles range from 3–9°. There are a spread of Cu–O bond distances ranging from 1.91–2.41 Å. There are fifteen inequivalent O2- sites. In the first O2- site, O2- is bonded to four La3+ and two equivalent Cu+2.33+ atoms to form distorted OLa4Cu2 octahedra that share corners with two equivalent OLa4Cu2 octahedra, corners with two equivalent OLa4 tetrahedra, edges with two equivalent OLa4Cu2 octahedra, and faces with six OLa4Cu2 octahedra. The corner-sharing octahedral tilt angles are 4°. In the second O2- site, O2- is bonded to five La3+ and one Cu+2.33+ atom to form distorted OLa5Cu octahedra that share corners with seven OLa4Cu2 octahedra, corners with four OLa3Cu tetrahedra, an edgeedge with one OLa5Cu octahedra, and faces with four OLa4Cu2 octahedra. The corner-sharing octahedra tilt angles range from 48–53°. In the third O2- site, O2- is bonded in a 6-coordinate geometry to five La3+ and one Cu+2.33+ atom. In the fourth O2- site, O2- is bonded to four La3+ and two Cu+2.33+ atoms to form distorted OLa4Cu2 octahedra that share corners with four OLa5Cu octahedra, a cornercorner with one OLa4 tetrahedra, an edgeedge with one OLa4Cu2 octahedra, an edgeedge with one OLa3Cu tetrahedra, and faces with four OLa4Cu2 octahedra. The corner-sharing octahedra tilt angles range from 4–51°. In the fifth O2- site, O2- is bonded to four La3+ and two equivalent Cu+2.33+ atoms to form distorted OLa4Cu2 octahedra that share corners with four equivalent OLa5Cu octahedra, corners with two equivalent OLa3Cu tetrahedra, edges with two equivalent OLa4Cu2 octahedra, an edgeedge with one OLa4 tetrahedra, and faces with four OLa4Cu2 octahedra. The corner-sharing octahedra tilt angles range from 52–53°. In the sixth O2- site, O2- is bonded in a 6-coordinate geometry to four La3+ and two equivalent Cu+2.33+ atoms. In the seventh O2- site, O2- is bonded to four La3+ and two Cu+2.33+ atoms to form distorted OLa4Cu2 octahedra that share corners with three OLa5Cu octahedra, corners with three OLa3Cu tetrahedra, edges with two OLa4Cu2 octahedra, an edgeedge with one OLa3Cu tetrahedra, and faces with four OLa4Cu2 octahedra. The corner-sharing octahedra tilt angles range from 4–51°. In the eighth O2- site, O2- is bonded to four La3+ and two Cu+2.33+ atoms to form distorted OLa4Cu2 octahedra that share corners with two OLa4Cu2 octahedra, corners with four OLa3Cu tetrahedra, and faces with four OLa5Cu octahedra. The corner-sharing octahedra tilt angles range from 4–48°. In the ninth O2- site, O2- is bonded to three La3+ and one Cu+2.33+ atom to form distorted OLa3Cu tetrahedra that share corners with nine OLa5Cu octahedra, a cornercorner with one OLa4 tetrahedra, and edges with two OLa4Cu2 octahedra. The corner-sharing octahedra tilt angles range from 32–83°. In the tenth O2- site, O2- is bonded in a 6-coordinate geometry to five La3+ and one Cu+2.33+ atom. In the eleventh O2- site, O2- is bonded in a distorted see-saw-like geometry to three La3+ and one Cu+2.33+ atom. In the twelfth O2- site, O2- is bonded in a 6-coordinate geometry to five La3+ and one Cu+2.33+ atom. In the thirteenth O2- site, O2- is bonded in a 6-coordinate geometry to four La3+ and two Cu+2.33+ atoms. In the fourteenth O2- site, O2- is bonded to four La3+ atoms to form OLa4 tetrahedra that share corners with fourteen OLa4Cu2 octahedra, corners with two equivalent OLa3Cu tetrahedra, and edges with two OLa4Cu2 octahedra. The corner-sharing octahedra tilt angles range from 8–69°. In the fifteenth O2- site, O2- is bonded to four La3+ and two equivalent Cu+2.33+ atoms to form distorted OLa4Cu2 octahedra that share corners with two equivalent OLa5Cu octahedra, corners with four equivalent OLa3Cu tetrahedra, edges with two equivalent OLa4Cu2 octahedra, an edgeedge with one OLa4 tetrahedra, and faces with two equivalent OLa4Cu2 octahedra. The corner-sharing octahedral tilt angles are 53°.

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2020-04-30. Materials Data on La12Cu6O25 by Materials Project. https://doi.org/10.17188/1290798

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