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DOE OSTI · 1675943

Materials Data on NaGa11O18 by Materials Project

Abstract

NaGa11O18 crystallizes in the monoclinic P2_1/m space group. The structure is three-dimensional. Na is bonded in a 2-coordinate geometry to seven O atoms. There are a spread of Na–O bond distances ranging from 2.26–2.95 Å. There are seven inequivalent Ga sites. In the first Ga site, Ga is bonded to six O atoms to form GaO6 octahedra that share corners with two GaO6 octahedra, corners with three GaO4 tetrahedra, and edges with four GaO6 octahedra. The corner-sharing octahedra tilt angles range from 52–54°. There are a spread of Ga–O bond distances ranging from 1.94–2.15 Å. In the second Ga site, Ga is bonded to six O atoms to form GaO6 octahedra that share corners with two equivalent GaO6 octahedra, corners with four GaO4 tetrahedra, and edges with four equivalent GaO6 octahedra. The corner-sharing octahedral tilt angles are 50°. There are a spread of Ga–O bond distances ranging from 1.93–2.08 Å. In the third Ga site, Ga is bonded to six O atoms to form GaO6 octahedra that share corners with two GaO6 octahedra, corners with three GaO4 tetrahedra, and edges with five GaO6 octahedra. The corner-sharing octahedra tilt angles range from 50–54°. There are a spread of Ga–O bond distances ranging from 1.95–2.12 Å. In the fourth Ga site, Ga is bonded to six O atoms to form GaO6 octahedra that share corners with three GaO6 octahedra, corners with four GaO4 tetrahedra, and edges with four equivalent GaO6 octahedra. The corner-sharing octahedra tilt angles range from 20–52°. There are a spread of Ga–O bond distances ranging from 1.93–2.09 Å. In the fifth Ga site, Ga is bonded to four O atoms to form GaO4 tetrahedra that share corners with six GaO6 octahedra and corners with two GaO4 tetrahedra. The corner-sharing octahedra tilt angles range from 54–60°. There are a spread of Ga–O bond distances ranging from 1.85–1.89 Å. In the sixth Ga site, Ga is bonded to four O atoms to form GaO4 tetrahedra that share corners with eight GaO6 octahedra and corners with two GaO4 tetrahedra. The corner-sharing octahedra tilt angles range from 52–67°. There are a spread of Ga–O bond distances ranging from 1.86–1.90 Å. In the seventh Ga site, Ga is bonded to six O atoms to form GaO6 octahedra that share a cornercorner with one GaO6 octahedra, corners with eight GaO4 tetrahedra, and edges with two equivalent GaO6 octahedra. The corner-sharing octahedral tilt angles are 20°. There are a spread of Ga–O bond distances ranging from 2.03–2.09 Å. There are twelve inequivalent O sites. In the first O site, O is bonded to one Na and three Ga atoms to form corner-sharing ONaGa3 trigonal pyramids. In the second O site, O is bonded to four Ga atoms to form distorted OGa4 trigonal pyramids that share corners with two ONaGa3 trigonal pyramids and an edgeedge with one OGa4 trigonal pyramid. In the third O site, O is bonded in a trigonal non-coplanar geometry to one Na and two equivalent Ga atoms. In the fourth O site, O is bonded in a trigonal non-coplanar geometry to three Ga atoms. In the fifth O site, O is bonded in a 4-coordinate geometry to one Na and three Ga atoms. In the sixth O site, O is bonded in a trigonal planar geometry to three Ga atoms. In the seventh O site, O is bonded in a 4-coordinate geometry to one Na and three Ga atoms. In the eighth O site, O is bonded in a trigonal planar geometry to three Ga atoms. In the ninth O site, O is bonded in a distorted rectangular see-saw-like geometry to four Ga atoms. In the tenth O site, O is bonded in a distorted trigonal planar geometry to one Na and three Ga atoms. In the eleventh O site, O is bonded in a rectangular see-saw-like geometry to four Ga atoms. In the twelfth O site, O is bonded in a trigonal planar geometry to three Ga atoms.

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2020-04-30. Materials Data on NaGa11O18 by Materials Project. https://doi.org/10.17188/1675943

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