Materials Data on Na2Nb3O6 by Materials Project

Abstract

Na2Nb3O6 crystallizes in the trigonal P-31c space group. The structure is three-dimensional. there are three inequivalent Na1+ sites. In the first Na1+ site, Na1+ is bonded to six equivalent O2- atoms to form distorted NaO6 octahedra that share corners with six equivalent NbO6 pentagonal pyramids, edges with three equivalent NaO6 octahedra, and edges with six equivalent NbO6 pentagonal pyramids. All Na–O bond lengths are 2.42 Å. In the second Na1+ site, Na1+ is bonded to six equivalent O2- atoms to form distorted NaO6 octahedra that share corners with six equivalent NbO6 pentagonal pyramids, edges with three equivalent NaO6 octahedra, and edges with six equivalent NbO6 pentagonal pyramids. There are three shorter (2.41 Å) and three longer (2.42 Å) Na–O bond lengths. In the third Na1+ site, Na1+ is bonded to six equivalent O2- atoms to form distorted NaO6 octahedra that share corners with six equivalent NbO6 pentagonal pyramids, edges with three equivalent NaO6 octahedra, and edges with six equivalent NbO6 pentagonal pyramids. All Na–O bond lengths are 2.41 Å. Nb+3.33+ is bonded to six O2- atoms to form distorted NbO6 pentagonal pyramids that share corners with four NaO6 octahedra, edges with four NaO6 octahedra, and edges with six equivalent NbO6 pentagonal pyramids. The corner-sharing octahedral tilt angles are 9°. There are a spread of Nb–O bond distances ranging from 2.12–2.15 Å. There are two inequivalent O2- sites. In the first O2- site, O2- is bonded to two Na1+ and three equivalent Nb+3.33+ atoms to form a mixture of face, edge, and corner-sharing ONa2Nb3 square pyramids. In the second O2- site, O2- is bonded to two equivalent Na1+ and three equivalent Nb+3.33+ atoms to form a mixture of face, edge, and corner-sharing ONa2Nb3 square pyramids.