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DOE OSTI · 1194650

Materials Data on BaTi18Mn3O38 by Materials Project

Abstract

BaTi18Mn3O38 crystallizes in the trigonal R-3 space group. The structure is three-dimensional. Ba2+ is bonded to twelve O2- atoms to form BaO12 cuboctahedra that share corners with six equivalent TiO6 octahedra, edges with six equivalent TiO6 octahedra, and faces with six equivalent TiO6 octahedra. The corner-sharing octahedral tilt angles are 42°. There are six shorter (2.85 Å) and six longer (2.90 Å) Ba–O bond lengths. There are three inequivalent Ti+3.78+ sites. In the first Ti+3.78+ site, Ti+3.78+ is bonded to six O2- atoms to form TiO6 octahedra that share a cornercorner with one BaO12 cuboctahedra, a cornercorner with one MnO6 octahedra, corners with three equivalent TiO6 octahedra, corners with two equivalent MnO4 tetrahedra, and edges with four TiO6 octahedra. The corner-sharing octahedra tilt angles range from 40–57°. There are a spread of Ti–O bond distances ranging from 1.87–2.13 Å. In the second Ti+3.78+ site, Ti+3.78+ is bonded to six O2- atoms to form TiO6 octahedra that share a cornercorner with one MnO6 octahedra, corners with five TiO6 octahedra, a cornercorner with one MnO4 tetrahedra, edges with three equivalent TiO6 octahedra, and a faceface with one BaO12 cuboctahedra. The corner-sharing octahedra tilt angles range from 14–54°. There are a spread of Ti–O bond distances ranging from 1.95–2.10 Å. In the third Ti+3.78+ site, Ti+3.78+ is bonded to six O2- atoms to form TiO6 octahedra that share corners with six TiO6 octahedra, a cornercorner with one MnO4 tetrahedra, an edgeedge with one BaO12 cuboctahedra, and edges with three equivalent TiO6 octahedra. The corner-sharing octahedra tilt angles range from 40–57°. There are a spread of Ti–O bond distances ranging from 1.97–2.08 Å. There are two inequivalent Mn2+ sites. In the first Mn2+ site, Mn2+ is bonded to six equivalent O2- atoms to form MnO6 octahedra that share corners with twelve TiO6 octahedra. The corner-sharing octahedra tilt angles range from 49–53°. All Mn–O bond lengths are 2.23 Å. In the second Mn2+ site, Mn2+ is bonded to four O2- atoms to form MnO4 tetrahedra that share corners with twelve TiO6 octahedra. The corner-sharing octahedra tilt angles range from 58–65°. There are three shorter (2.03 Å) and one longer (2.09 Å) Mn–O bond lengths. There are seven inequivalent O2- sites. In the first O2- site, O2- is bonded to three equivalent Ti+3.78+ and one Mn2+ atom to form distorted corner-sharing OTi3Mn tetrahedra. In the second O2- site, O2- is bonded in a distorted T-shaped geometry to one Ba2+ and three Ti+3.78+ atoms. In the third O2- site, O2- is bonded to three Ti+3.78+ and one Mn2+ atom to form a mixture of distorted edge and corner-sharing OTi3Mn tetrahedra. In the fourth O2- site, O2- is bonded in a distorted trigonal planar geometry to three Ti+3.78+ atoms. In the fifth O2- site, O2- is bonded in a distorted trigonal planar geometry to three Ti+3.78+ atoms. In the sixth O2- site, O2- is bonded in a distorted trigonal planar geometry to two Ti+3.78+ and one Mn2+ atom. In the seventh O2- site, O2- is bonded in a 3-coordinate geometry to one Ba2+ and three Ti+3.78+ atoms.

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2020-04-30. Materials Data on BaTi18Mn3O38 by Materials Project. https://doi.org/10.17188/1194650

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