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DOE OSTI · 1475639

Materials Data on La6Sm2Co7AgO24 by Materials Project

Abstract

Sm2La6Co7AgO24 is (Cubic) Perovskite-derived structured and crystallizes in the orthorhombic Amm2 space group. The structure is three-dimensional. Sm3+ is bonded to twelve O2- atoms to form SmO12 cuboctahedra that share corners with twelve LaO12 cuboctahedra, faces with two equivalent SmO12 cuboctahedra, faces with four equivalent LaO12 cuboctahedra, a faceface with one AgO6 octahedra, and faces with seven CoO6 octahedra. There are a spread of Sm–O bond distances ranging from 2.64–2.71 Å. There are two inequivalent La3+ sites. In the first La3+ site, La3+ is bonded to twelve O2- atoms to form LaO12 cuboctahedra that share corners with four equivalent SmO12 cuboctahedra, corners with eight LaO12 cuboctahedra, faces with two equivalent SmO12 cuboctahedra, faces with four LaO12 cuboctahedra, a faceface with one AgO6 octahedra, and faces with seven CoO6 octahedra. There are a spread of La–O bond distances ranging from 2.68–2.79 Å. In the second La3+ site, La3+ is bonded to twelve O2- atoms to form LaO12 cuboctahedra that share corners with four equivalent SmO12 cuboctahedra, corners with eight equivalent LaO12 cuboctahedra, faces with six LaO12 cuboctahedra, a faceface with one AgO6 octahedra, and faces with seven CoO6 octahedra. There are a spread of La–O bond distances ranging from 2.68–2.82 Å. There are five inequivalent Co+3.29+ sites. In the first Co+3.29+ site, Co+3.29+ is bonded to six O2- atoms to form CoO6 octahedra that share corners with six CoO6 octahedra, faces with two equivalent SmO12 cuboctahedra, and faces with six LaO12 cuboctahedra. The corner-sharing octahedra tilt angles range from 0–2°. There are a spread of Co–O bond distances ranging from 1.89–1.94 Å. In the second Co+3.29+ site, Co+3.29+ is bonded to six O2- atoms to form CoO6 octahedra that share corners with six CoO6 octahedra, faces with two equivalent SmO12 cuboctahedra, and faces with six LaO12 cuboctahedra. The corner-sharing octahedra tilt angles range from 0–2°. There are a spread of Co–O bond distances ranging from 1.90–1.92 Å. In the third Co+3.29+ site, Co+3.29+ is bonded to six O2- atoms to form CoO6 octahedra that share corners with two equivalent AgO6 octahedra, corners with four CoO6 octahedra, faces with two equivalent SmO12 cuboctahedra, and faces with six LaO12 cuboctahedra. The corner-sharing octahedra tilt angles range from 0–4°. There are a spread of Co–O bond distances ranging from 1.81–1.94 Å. In the fourth Co+3.29+ site, Co+3.29+ is bonded to six O2- atoms to form CoO6 octahedra that share corners with six CoO6 octahedra, faces with two equivalent SmO12 cuboctahedra, and faces with six LaO12 cuboctahedra. The corner-sharing octahedra tilt angles range from 0–3°. There are a spread of Co–O bond distances ranging from 1.90–1.93 Å. In the fifth Co+3.29+ site, Co+3.29+ is bonded to six O2- atoms to form CoO6 octahedra that share corners with two equivalent AgO6 octahedra, corners with four equivalent CoO6 octahedra, faces with two equivalent SmO12 cuboctahedra, and faces with six LaO12 cuboctahedra. The corner-sharing octahedra tilt angles range from 0–5°. There are a spread of Co–O bond distances ranging from 1.84–1.93 Å. Ag1+ is bonded to six O2- atoms to form AgO6 octahedra that share corners with six CoO6 octahedra, faces with two equivalent SmO12 cuboctahedra, and faces with six LaO12 cuboctahedra. The corner-sharing octahedra tilt angles range from 1–5°. There are two shorter (2.01 Å) and four longer (2.02 Å) Ag–O bond lengths. There are eleven inequivalent O2- sites. In the first O2- site, O2- is bonded in a distorted linear geometry to four La3+ and two Co+3.29+ atoms. In the second O2- site, O2- is bonded in a distorted linear geometry to four La3+ and two Co+3.29+ atoms. In the third O2- site, O2- is bonded in a distorted linear geometry to four La3+, one Co+3.29+, and one Ag1+ atom. In the fourth O2- site, O2- is bonded in a distorted linear geometry to four La3+ and two Co+3.29+ atoms. In the fifth O2- site, O2- is bonded in a distorted linear geometry to two equivalent Sm3+, two equivalent La3+, and two Co+3.29+ atoms. In the sixth O2- site, O2- is bonded in a distorted linear geometry to two equivalent Sm3+, two equivalent La3+, and two Co+3.29+ atoms. In the seventh O2- site, O2- is bonded in a distorted linear geometry to two equivalent Sm3+, two equivalent La3+, one Co+3.29+, and one Ag1+ atom. In the eighth O2- site, O2- is bonded in a distorted linear geometry to two equivalent Sm3+, two equivalent La3+, and two Co+3.29+ atoms. In the ninth O2- site, O2- is bonded in a distorted linear geometry to one Sm3+, three La3+, and two Co+3.29+ atoms. In the tenth O2- site, O2- is bonded in a distorted linear geometry to one Sm3+, three La3+, and two Co+3.29+ atoms. In the eleventh O2- site, O2- is bonded in a distorted linear geometry to one Sm3+, three La3+, one Co+3.29+, and one Ag1+ atom.

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2020-07-15. Materials Data on La6Sm2Co7AgO24 by Materials Project. https://doi.org/10.17188/1475639

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