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All sourcesNASA NTRSDOE OSTI
DOE OSTI2020

Materials Data on NaNbWO6 by Materials Project

NaNbWO6 crystallizes in the orthorhombic Imma space group. The structure is three-dimensional. Na1+ is bonded in a hexagonal planar geometry to six O2- atoms. There are two shorter (2.64 Å) and four longer (2.69 Å) Na–O bond lengths. Nb5+ is bonded to six O2- atoms to form NbO6 octahedra that share corners with two equivalent NbO6 octahedra and corners with four equivalent WO6 octahedra. The corner-sharing octahedra tilt angles range from 39–44°. All Nb–O bond lengths are 2.00 Å. W6+ is bonded to six O2- atoms to form WO6 octahedra that share corners with two equivalent WO6 octahedra and corners with four equivalent NbO6 octahedra. The corner-sharing octahedra tilt angles range from 35–39°. There is four shorter (1.93 Å) and two longer (1.95 Å) W–O bond length. There are three inequivalent O2- sites. In the first O2- site, O2- is bonded in a 2-coordinate geometry to one Na1+, one Nb5+, and one W6+ atom. In the second O2- site, O2- is bonded in a bent 150 degrees geometry to two equivalent W6+ atoms. In the third O2- site, O2- is bonded in a 4-coordinate geometry to two equivalent Na1+ and two equivalent Nb5+ atoms.

36 MATERIALS SCIENCE↗
DOE OSTI2020

Materials Data on Na2Nb2W2O13 by Materials Project

Na2Nb2W2O13 crystallizes in the orthorhombic Imm2 space group. The structure is three-dimensional. Na is bonded to seven O atoms to form NaO7 hexagonal pyramids that share a cornercorner with one NaO7 hexagonal pyramid, an edgeedge with one NaO7 hexagonal pyramid, edges with two equivalent WO6 octahedra, and edges with four equivalent NbO6 octahedra. There are a spread of Na–O bond distances ranging from 2.56–2.71 Å. Nb is bonded to six O atoms to form NbO6 octahedra that share corners with two equivalent NbO6 octahedra, corners with four equivalent WO6 octahedra, and edges with four equivalent NaO7 hexagonal pyramids. The corner-sharing octahedra tilt angles range from 37–45°. There are a spread of Nb–O bond distances ranging from 1.98–2.03 Å. W is bonded to six O atoms to form WO6 octahedra that share corners with two equivalent WO6 octahedra, corners with four equivalent NbO6 octahedra, and edges with two equivalent NaO7 hexagonal pyramids. The corner-sharing octahedra tilt angles range from 34–39°. There are a spread of W–O bond distances ranging from 1.92–1.98 Å. There are seven inequivalent O sites. In the first O site, O is bonded in a 3-coordinate geometry to one Na, one Nb, and one W atom. In the second O site, O is bonded in a bent 150 degrees geometry to two equivalent W atoms. In the third O site, O is bonded in a 4-coordinate geometry to two equivalent Na and two equivalent Nb atoms. In the fourth O site, O is bonded in a 3-coordinate geometry to one Na, one Nb, and one W atom. In the fifth O site, O is bonded in a bent 150 degrees geometry to two equivalent W atoms. In the sixth O site, O is bonded in a 4-coordinate geometry to two equivalent Na and two equivalent Nb atoms. In the seventh O site, O is bonded in an L-shaped geometry to two equivalent Na atoms.

36 MATERIALS SCIENCE↗
DOE OSTI2020

Materials Data on NaNbWO7 by Materials Project

NaNbWO7 crystallizes in the orthorhombic Imma space group. The structure is three-dimensional. Na is bonded to eight O atoms to form distorted NaO8 hexagonal bipyramids that share edges with two equivalent NaO8 hexagonal bipyramids, edges with two equivalent WO6 octahedra, and edges with four equivalent NbO6 octahedra. There are a spread of Na–O bond distances ranging from 2.32–2.73 Å. Nb is bonded to six O atoms to form NbO6 octahedra that share corners with two equivalent NbO6 octahedra, corners with four equivalent WO6 octahedra, and edges with four equivalent NaO8 hexagonal bipyramids. The corner-sharing octahedra tilt angles range from 38–43°. There are four shorter (2.00 Å) and two longer (2.01 Å) Nb–O bond lengths. W is bonded to six O atoms to form WO6 octahedra that share corners with two equivalent WO6 octahedra, corners with four equivalent NbO6 octahedra, and edges with two equivalent NaO8 hexagonal bipyramids. The corner-sharing octahedra tilt angles range from 35–38°. There is four shorter (1.93 Å) and two longer (1.97 Å) W–O bond length. There are four inequivalent O sites. In the first O site, O is bonded in a water-like geometry to two equivalent Na atoms. In the second O site, O is bonded in a 3-coordinate geometry to one Na, one Nb, and one W atom. In the third O site, O is bonded in a bent 150 degrees geometry to two equivalent W atoms. In the fourth O site, O is bonded in a 4-coordinate geometry to two equivalent Na and two equivalent Nb atoms.

36 MATERIALS SCIENCE↗