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DOE OSTI · 1718479

Materials Data on Ba4CaMn2MoO12 by Materials Project

Abstract

Ba4CaMoMn2O12 crystallizes in the trigonal R3m space group. The structure is three-dimensional. there are four inequivalent Ba2+ sites. In the first Ba2+ site, Ba2+ is bonded to twelve O2- atoms to form BaO12 cuboctahedra that share corners with nine BaO12 cuboctahedra, corners with three equivalent MoO6 octahedra, faces with four BaO12 cuboctahedra, a faceface with one CaO6 octahedra, and faces with six MnO6 octahedra. The corner-sharing octahedral tilt angles are 8°. There are a spread of Ba–O bond distances ranging from 2.97–3.08 Å. In the second Ba2+ site, Ba2+ is bonded to twelve O2- atoms to form distorted BaO12 cuboctahedra that share corners with six equivalent BaO12 cuboctahedra, corners with three equivalent MnO6 octahedra, faces with six BaO12 cuboctahedra, a faceface with one CaO6 octahedra, faces with three equivalent MoO6 octahedra, and faces with three equivalent MnO6 octahedra. The corner-sharing octahedral tilt angles are 6°. There are a spread of Ba–O bond distances ranging from 2.91–3.15 Å. In the third Ba2+ site, Ba2+ is bonded to twelve O2- atoms to form BaO12 cuboctahedra that share corners with nine BaO12 cuboctahedra, corners with three equivalent MnO6 octahedra, faces with four BaO12 cuboctahedra, a faceface with one MnO6 octahedra, faces with three equivalent CaO6 octahedra, and faces with three equivalent MoO6 octahedra. The corner-sharing octahedral tilt angles are 13°. There are a spread of Ba–O bond distances ranging from 2.90–3.23 Å. In the fourth Ba2+ site, Ba2+ is bonded in a 9-coordinate geometry to nine O2- atoms. There are three shorter (2.78 Å) and six longer (2.99 Å) Ba–O bond lengths. Ca2+ is bonded to six O2- atoms to form CaO6 octahedra that share corners with three equivalent MoO6 octahedra, corners with three equivalent MnO6 octahedra, and faces with five BaO12 cuboctahedra. The corner-sharing octahedra tilt angles range from 0–11°. There are three shorter (2.21 Å) and three longer (2.35 Å) Ca–O bond lengths. Mo6+ is bonded to six O2- atoms to form MoO6 octahedra that share corners with three equivalent BaO12 cuboctahedra, corners with three equivalent CaO6 octahedra, faces with six BaO12 cuboctahedra, and a faceface with one MnO6 octahedra. The corner-sharing octahedral tilt angles are 11°. There is three shorter (1.85 Å) and three longer (2.07 Å) Mo–O bond length. There are two inequivalent Mn4+ sites. In the first Mn4+ site, Mn4+ is bonded to six O2- atoms to form MnO6 octahedra that share corners with three equivalent BaO12 cuboctahedra, faces with six BaO12 cuboctahedra, a faceface with one MoO6 octahedra, and a faceface with one MnO6 octahedra. There is three shorter (1.91 Å) and three longer (1.97 Å) Mn–O bond length. In the second Mn4+ site, Mn4+ is bonded to six O2- atoms to form MnO6 octahedra that share corners with three equivalent BaO12 cuboctahedra, corners with three equivalent CaO6 octahedra, faces with four BaO12 cuboctahedra, and a faceface with one MnO6 octahedra. The corner-sharing octahedral tilt angles are 0°. There is three shorter (1.86 Å) and three longer (2.07 Å) Mn–O bond length. There are four inequivalent O2- sites. In the first O2- site, O2- is bonded in a distorted linear geometry to four Ba2+, one Ca2+, and one Mn4+ atom. In the second O2- site, O2- is bonded in a 6-coordinate geometry to four Ba2+ and two Mn4+ atoms. In the third O2- site, O2- is bonded in a 2-coordinate geometry to four Ba2+, one Mo6+, and one Mn4+ atom. In the fourth O2- site, O2- is bonded in a 2-coordinate geometry to three Ba2+, one Ca2+, and one Mo6+ atom.

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2020-06-05. Materials Data on Ba4CaMn2MoO12 by Materials Project. https://doi.org/10.17188/1718479

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