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DOE OSTI · 1475720

Materials Data on La7SmCr2(FeO4)6 by Materials Project

Abstract

SmLa7Cr2(FeO4)6 is (Cubic) Perovskite-derived structured and crystallizes in the orthorhombic Cmm2 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 six LaO12 cuboctahedra, faces with two equivalent CrO6 octahedra, and faces with six FeO6 octahedra. All Sm–O bond lengths are 2.78 Å. There are five inequivalent La3+ sites. In the first La3+ site, La3+ is bonded to twelve O2- atoms to form LaO12 cuboctahedra that share corners with twelve LaO12 cuboctahedra, faces with two equivalent SmO12 cuboctahedra, faces with four LaO12 cuboctahedra, faces with two equivalent CrO6 octahedra, and faces with six FeO6 octahedra. There are four shorter (2.78 Å) and eight longer (2.79 Å) La–O bond lengths. 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, faces with two equivalent CrO6 octahedra, and faces with six FeO6 octahedra. There are four shorter (2.78 Å) and eight longer (2.79 Å) La–O bond lengths. In the third 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 six LaO12 cuboctahedra, faces with two equivalent CrO6 octahedra, and faces with six FeO6 octahedra. There are two shorter (2.78 Å) and ten longer (2.79 Å) La–O bond lengths. In the fourth La3+ site, La3+ is bonded to twelve O2- atoms to form LaO12 cuboctahedra that share corners with twelve LaO12 cuboctahedra, faces with six LaO12 cuboctahedra, faces with two equivalent CrO6 octahedra, and faces with six FeO6 octahedra. There are four shorter (2.78 Å) and eight longer (2.79 Å) La–O bond lengths. In the fifth La3+ site, La3+ is bonded to twelve O2- atoms to form LaO12 cuboctahedra that share corners with twelve LaO12 cuboctahedra, faces with two equivalent SmO12 cuboctahedra, faces with four equivalent LaO12 cuboctahedra, faces with two equivalent CrO6 octahedra, and faces with six FeO6 octahedra. There are four shorter (2.78 Å) and eight longer (2.79 Å) La–O bond lengths. Cr3+ is bonded to six O2- atoms to form CrO6 octahedra that share corners with six FeO6 octahedra, a faceface with one SmO12 cuboctahedra, and faces with seven LaO12 cuboctahedra. The corner-sharing octahedral tilt angles are 0°. There is one shorter (1.96 Å) and five longer (1.97 Å) Cr–O bond length. There are three inequivalent Fe3+ sites. In the first Fe3+ site, Fe3+ is bonded to six O2- atoms to form FeO6 octahedra that share corners with six FeO6 octahedra, a faceface with one SmO12 cuboctahedra, and faces with seven LaO12 cuboctahedra. The corner-sharing octahedral tilt angles are 0°. All Fe–O bond lengths are 1.97 Å. In the second Fe3+ site, Fe3+ is bonded to six O2- atoms to form FeO6 octahedra that share corners with two equivalent CrO6 octahedra, corners with four equivalent FeO6 octahedra, a faceface with one SmO12 cuboctahedra, and faces with seven LaO12 cuboctahedra. The corner-sharing octahedral tilt angles are 0°. There is five shorter (1.97 Å) and one longer (1.98 Å) Fe–O bond length. In the third Fe3+ site, Fe3+ is bonded to six O2- atoms to form FeO6 octahedra that share corners with two equivalent FeO6 octahedra, corners with four equivalent CrO6 octahedra, a faceface with one SmO12 cuboctahedra, and faces with seven LaO12 cuboctahedra. The corner-sharing octahedral tilt angles are 0°. All Fe–O bond lengths are 1.97 Å. There are eight inequivalent O2- sites. In the first O2- site, O2- is bonded in a distorted linear geometry to four La3+ and two Fe3+ atoms. In the second O2- site, O2- is bonded in a distorted linear geometry to four La3+, one Cr3+, and one Fe3+ atom. In the third O2- site, O2- is bonded in a distorted linear geometry to one Sm3+, three La3+, and two Fe3+ atoms. In the fourth O2- site, O2- is bonded in a distorted linear geometry to one Sm3+, three La3+, one Cr3+, and one Fe3+ atom. In the fifth O2- site, O2- is bonded in a distorted linear geometry to one Sm3+, three La3+, and two Fe3+ atoms. In the sixth O2- site, O2- is bonded in a distorted linear geometry to one Sm3+, three La3+, one Cr3+, and one Fe3+ atom. In the seventh O2- site, O2- is bonded in a distorted linear geometry to four La3+ and two Fe3+ atoms. In the eighth O2- site, O2- is bonded in a distorted linear geometry to four La3+, one Cr3+, and one Fe3+ atom.

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BibTeXRIS

2020-04-29. Materials Data on La7SmCr2(FeO4)6 by Materials Project. https://doi.org/10.17188/1475720

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