Materials Data on Na2NbF6 by Materials Project
Na2NbF6 is Hydrophilite-derived structured and crystallizes in the tetragonal P4_2/mnm space group. The structure is three-dimensional. Na1+ is bonded to six F1- atoms to form NaF6 octahedra that share corners with four equivalent NaF6 octahedra, corners with four equivalent NbF6 octahedra, an edgeedge with one NaF6 octahedra, and an edgeedge with one NbF6 octahedra. The corner-sharing octahedra tilt angles range from 44–61°. There are a spread of Na–F bond distances ranging from 2.29–2.41 Å. Nb4+ is bonded to six F1- atoms to form NbF6 octahedra that share corners with eight equivalent NaF6 octahedra and edges with two equivalent NaF6 octahedra. The corner-sharing octahedra tilt angles range from 44–47°. There are two shorter (1.97 Å) and four longer (2.04 Å) Nb–F bond lengths. There are two inequivalent F1- sites. In the first F1- site, F1- is bonded in a 3-coordinate geometry to two equivalent Na1+ and one Nb4+ atom. In the second F1- site, F1- is bonded in a distorted trigonal planar geometry to two equivalent Na1+ and one Nb4+ atom.