Materials Data on NaNb14O36 by Materials Project

Abstract

NaNb14O36 crystallizes in the orthorhombic Immm space group. The structure is three-dimensional. Na is bonded in a square co-planar geometry to four equivalent O atoms. All Na–O bond lengths are 2.55 Å. There are five inequivalent Nb sites. In the first Nb site, Nb is bonded in a 6-coordinate geometry to six O atoms. There are a spread of Nb–O bond distances ranging from 1.80–2.40 Å. In the second Nb site, Nb is bonded to six O atoms to form a mixture of distorted corner and edge-sharing NbO6 octahedra. The corner-sharing octahedra tilt angles range from 6–31°. There are a spread of Nb–O bond distances ranging from 1.84–2.29 Å. In the third Nb site, Nb is bonded to six O atoms to form corner-sharing NbO6 octahedra. The corner-sharing octahedra tilt angles range from 7–16°. There are a spread of Nb–O bond distances ranging from 1.92–2.16 Å. In the fourth Nb site, Nb is bonded in a 6-coordinate geometry to six O atoms. There are a spread of Nb–O bond distances ranging from 1.82–2.37 Å. In the fifth Nb site, Nb is bonded to six O atoms to form corner-sharing NbO6 octahedra. The corner-sharing octahedra tilt angles range from 6–13°. There are four shorter (1.96 Å) and two longer (2.08 Å) Nb–O bond lengths. There are eleven inequivalent O sites. In the first O site, O is bonded in a linear geometry to two equivalent Nb atoms. In the second O site, O is bonded in a linear geometry to two Nb atoms. In the third O site, O is bonded in a linear geometry to two Nb atoms. In the fourth O site, O is bonded in a linear geometry to two Nb atoms. In the fifth O site, O is bonded in a linear geometry to two Nb atoms. In the sixth O site, O is bonded in a 3-coordinate geometry to three Nb atoms. In the seventh O site, O is bonded in a 3-coordinate geometry to three equivalent Nb atoms. In the eighth O site, O is bonded in a linear geometry to two equivalent Nb atoms. In the ninth O site, O is bonded to two equivalent Na and two equivalent Nb atoms to form ONa2Nb2 tetrahedra that share corners with four equivalent ONa2Nb2 tetrahedra, an edgeedge with one ONa2Nb2 tetrahedra, and an edgeedge with one ONb4 trigonal pyramid. In the tenth O site, O is bonded to four Nb atoms to form distorted ONb4 trigonal pyramids that share corners with two equivalent ONb4 trigonal pyramids and an edgeedge with one ONa2Nb2 tetrahedra. In the eleventh O site, O is bonded in a linear geometry to two Nb atoms.