DOI: 10.17188/1296192
title: Materials Data on Na5(NiO2)6 by Materials Project

description: Na5(NiO2)6 crystallizes in the triclinic P-1 space group. The structure is three-dimensional. there are three inequivalent Na1+ sites. In the first Na1+ site, Na1+ is bonded to six O2- atoms to form distorted NaO6 octahedra that share corners with six NiO6 octahedra, edges with five NaO6 octahedra, and edges with six NiO6 octahedra. The corner-sharing octahedra tilt angles range from 10–17°. There are a spread of Na–O bond distances ranging from 2.33–2.40 Å. In the second Na1+ site, Na1+ is bonded to six O2- atoms to form distorted NaO6 octahedra that share corners with six NiO6 octahedra, edges with four NaO6 octahedra, and edges with six NiO6 octahedra. The corner-sharing octahedra tilt angles range from 12–17°. There are a spread of Na–O bond distances ranging from 2.33–2.44 Å. In the third Na1+ site, Na1+ is bonded to six O2- atoms to form distorted NaO6 octahedra that share corners with six NiO6 octahedra, edges with five NaO6 octahedra, and edges with six NiO6 octahedra. The corner-sharing octahedra tilt angles range from 9–17°. There are a spread of Na–O bond distances ranging from 2.28–2.43 Å. There are three inequivalent Ni+3.17+ sites. In the first Ni+3.17+ site, Ni+3.17+ is bonded to six O2- atoms to form NiO6 octahedra that share corners with six NaO6 octahedra, edges with five NaO6 octahedra, and edges with six NiO6 octahedra. The corner-sharing octahedra tilt angles range from 10–17°. There are a spread of Ni–O bond distances ranging from 1.91–2.16 Å. In the second Ni+3.17+ site, Ni+3.17+ is bonded to six O2- atoms to form NiO6 octahedra that share corners with five NaO6 octahedra, edges with five NaO6 octahedra, and edges with six NiO6 octahedra. The corner-sharing octahedra tilt angles range from 11–17°. There are a spread of Ni–O bond distances ranging from 1.90–2.16 Å. In the third Ni+3.17+ site, Ni+3.17+ is bonded to six O2- atoms to form NiO6 octahedra that share corners with four NaO6 octahedra, edges with five NaO6 octahedra, and edges with six NiO6 octahedra. The corner-sharing octahedra tilt angles range from 9–17°. There are a spread of Ni–O bond distances ranging from 1.91–2.05 Å. There are six inequivalent O2- sites. In the first O2- site, O2- is bonded to three Na1+ and three Ni+3.17+ atoms to form ONa3Ni3 octahedra that share corners with three ONa3Ni3 octahedra, corners with three ONa2Ni3 square pyramids, edges with six ONa3Ni3 octahedra, and edges with six ONa2Ni3 square pyramids. The corner-sharing octahedra tilt angles range from 1–7°. In the second O2- site, O2- is bonded to two Na1+ and three Ni+3.17+ atoms to form ONa2Ni3 square pyramids that share corners with two ONa3Ni3 octahedra, corners with seven ONa2Ni3 square pyramids, edges with six ONa3Ni3 octahedra, and edges with two ONa2Ni3 square pyramids. The corner-sharing octahedra tilt angles range from 3–8°. In the third O2- site, O2- is bonded to two Na1+ and three Ni+3.17+ atoms to form distorted ONa2Ni3 square pyramids that share a cornercorner with one ONa3Ni3 octahedra, corners with eight ONa2Ni3 square pyramids, edges with six ONa3Ni3 octahedra, and edges with two ONa2Ni3 square pyramids. The corner-sharing octahedral tilt angles are 7°. In the fourth O2- site, O2- is bonded to three Na1+ and three Ni+3.17+ atoms to form ONa3Ni3 octahedra that share corners with three ONa3Ni3 octahedra, corners with three ONa2Ni3 square pyramids, edges with six ONa3Ni3 octahedra, and edges with six ONa2Ni3 square pyramids. The corner-sharing octahedral tilt angles are 1°. In the fifth O2- site, O2- is bonded to three Na1+ and three Ni+3.17+ atoms to form ONa3Ni3 octahedra that share corners with five ONa3Ni3 octahedra, a cornercorner with one ONa2Ni3 square pyramid, edges with five ONa3Ni3 octahedra, and edges with seven ONa2Ni3 square pyramids. The corner-sharing octahedra tilt angles range from 0–7°. In the sixth O2- site, O2- is bonded to two Na1+ and three Ni+3.17+ atoms to form ONa2Ni3 square pyramids that share corners with four ONa3Ni3 octahedra, corners with five ONa2Ni3 square pyramids, edges with seven ONa3Ni3 octahedra, and an edgeedge with one ONa2Ni3 square pyramid. The corner-sharing octahedra tilt angles range from 1–6°.