Materials Data on Na6NiO4 by Materials Project

Abstract

Na6NiO4 crystallizes in the monoclinic Cc space group. The structure is three-dimensional. there are six inequivalent Na1+ sites. In the first Na1+ site, Na1+ is bonded in a 4-coordinate geometry to four O2- atoms. There are a spread of Na–O bond distances ranging from 2.33–2.58 Å. In the second Na1+ site, Na1+ is bonded in a 5-coordinate geometry to five O2- atoms. There are a spread of Na–O bond distances ranging from 2.34–2.75 Å. In the third Na1+ site, Na1+ is bonded to four O2- atoms to form distorted NaO4 trigonal pyramids that share corners with two equivalent NiO4 tetrahedra, corners with six NaO4 trigonal pyramids, and an edgeedge with one NiO4 tetrahedra. There are a spread of Na–O bond distances ranging from 2.36–2.56 Å. In the fourth Na1+ site, Na1+ is bonded in a 5-coordinate geometry to five O2- atoms. There are a spread of Na–O bond distances ranging from 2.35–2.72 Å. In the fifth Na1+ site, Na1+ is bonded in a 3-coordinate geometry to five O2- atoms. There are a spread of Na–O bond distances ranging from 2.34–2.75 Å. In the sixth Na1+ site, Na1+ is bonded to four O2- atoms to form distorted NaO4 trigonal pyramids that share corners with two equivalent NiO4 tetrahedra, corners with four equivalent NaO4 trigonal pyramids, and an edgeedge with one NiO4 tetrahedra. There are a spread of Na–O bond distances ranging from 2.35–2.55 Å. Ni2+ is bonded to four O2- atoms to form NiO4 tetrahedra that share corners with four NaO4 trigonal pyramids and edges with two NaO4 trigonal pyramids. There are a spread of Ni–O bond distances ranging from 1.98–2.06 Å. There are four inequivalent O2- sites. In the first O2- site, O2- is bonded in a 6-coordinate geometry to seven Na1+ and one Ni2+ atom. In the second O2- site, O2- is bonded in a 8-coordinate geometry to seven Na1+ and one Ni2+ atom. In the third O2- site, O2- is bonded in a 7-coordinate geometry to six Na1+ and one Ni2+ atom. In the fourth O2- site, O2- is bonded in a 8-coordinate geometry to seven Na1+ and one Ni2+ atom.