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DOE OSTI · 1267902

Materials Data on NaTi2Ga5O12 by Materials Project

Abstract

NaTi2Ga5O12 crystallizes in the orthorhombic Pbam space group. The structure is three-dimensional. Na1+ is bonded in a 6-coordinate geometry to six O2- atoms. There are two shorter (2.51 Å) and four longer (2.63 Å) Na–O bond lengths. Ti4+ is bonded to six O2- atoms to form distorted TiO6 octahedra that share corners with four GaO6 octahedra, a cornercorner with one GaO4 tetrahedra, edges with two equivalent TiO6 octahedra, and edges with two equivalent GaO6 octahedra. The corner-sharing octahedral tilt angles are 50°. There are a spread of Ti–O bond distances ranging from 1.83–2.21 Å. There are three inequivalent Ga3+ sites. In the first Ga3+ site, Ga3+ is bonded to six O2- atoms to form GaO6 octahedra that share corners with four equivalent TiO6 octahedra, corners with four equivalent GaO4 tetrahedra, and edges with two equivalent GaO6 octahedra. The corner-sharing octahedral tilt angles are 50°. There is two shorter (1.96 Å) and four longer (2.01 Å) Ga–O bond length. In the second Ga3+ site, Ga3+ is bonded to six O2- atoms to form GaO6 octahedra that share corners with two equivalent TiO6 octahedra, corners with four equivalent GaO4 tetrahedra, edges with two equivalent TiO6 octahedra, and edges with two equivalent GaO6 octahedra. The corner-sharing octahedral tilt angles are 50°. There are a spread of Ga–O bond distances ranging from 1.99–2.09 Å. In the third Ga3+ site, Ga3+ is bonded to four O2- atoms to form GaO4 tetrahedra that share a cornercorner with one TiO6 octahedra, corners with six GaO6 octahedra, and corners with two equivalent GaO4 tetrahedra. The corner-sharing octahedra tilt angles range from 56–67°. There are a spread of Ga–O bond distances ranging from 1.83–1.88 Å. There are six inequivalent O2- sites. In the first O2- site, O2- is bonded in a distorted trigonal planar geometry to one Ti4+ and two equivalent Ga3+ atoms. In the second O2- site, O2- is bonded in a trigonal planar geometry to three Ga3+ atoms. In the third O2- site, O2- is bonded to one Na1+ and three Ga3+ atoms to form distorted ONaGa3 tetrahedra that share corners with two equivalent ONa2Ti2Ga square pyramids, corners with three equivalent ONaGa3 tetrahedra, and edges with two equivalent ONa2Ti2Ga square pyramids. In the fourth O2- site, O2- is bonded in a distorted trigonal planar geometry to two equivalent Ti4+ and one Ga3+ atom. In the fifth O2- site, O2- is bonded to two equivalent Na1+, two equivalent Ti4+, and one Ga3+ atom to form distorted ONa2Ti2Ga square pyramids that share corners with two equivalent ONa2Ti2Ga square pyramids, corners with two equivalent ONaGa3 tetrahedra, edges with three equivalent ONa2Ti2Ga square pyramids, and edges with two equivalent ONaGa3 tetrahedra. In the sixth O2- site, O2- is bonded in a distorted rectangular see-saw-like geometry to one Ti4+ and three Ga3+ atoms.

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2020-07-20. Materials Data on NaTi2Ga5O12 by Materials Project. https://doi.org/10.17188/1267902

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