Materials Data on Na2O by Materials Project

Abstract

Na2O crystallizes in the trigonal P321 space group. The structure is three-dimensional. there are three inequivalent Na1+ sites. In the first Na1+ site, Na1+ is bonded to five O2- atoms to form distorted NaO5 square pyramids that share corners with ten equivalent NaO5 square pyramids, corners with six equivalent NaO4 tetrahedra, edges with six NaO5 square pyramids, and edges with six equivalent NaO4 tetrahedra. There are a spread of Na–O bond distances ranging from 2.55–2.62 Å. In the second Na1+ site, Na1+ is bonded to four O2- atoms to form distorted NaO4 tetrahedra that share corners with six NaO5 square pyramids, corners with ten equivalent NaO4 tetrahedra, edges with six NaO5 square pyramids, and edges with two equivalent NaO4 tetrahedra. There are two shorter (2.32 Å) and two longer (2.44 Å) Na–O bond lengths. In the third Na1+ site, Na1+ is bonded to five O2- atoms to form distorted NaO5 square pyramids that share corners with ten NaO5 square pyramids, corners with six equivalent NaO4 tetrahedra, edges with six NaO5 square pyramids, and edges with six equivalent NaO4 tetrahedra. There are a spread of Na–O bond distances ranging from 2.55–2.62 Å. There are two inequivalent O2- sites. In the first O2- site, O2- is bonded in a 9-coordinate geometry to nine Na1+ atoms. In the second O2- site, O2- is bonded in a 9-coordinate geometry to nine Na1+ atoms.