Materials Data on Na5CuO4 by Materials Project

Abstract

Na5CuO4 crystallizes in the orthorhombic Pbca space group. The structure is three-dimensional. there are five 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 2.26–2.67 Å. In the second Na1+ site, Na1+ is bonded in a distorted see-saw-like geometry to four O2- atoms. There are a spread of Na–O bond distances ranging from 2.38–2.45 Å. In the third Na1+ site, Na1+ is bonded to four O2- atoms to form distorted NaO4 tetrahedra that share corners with two equivalent CuO4 tetrahedra, corners with five NaO4 tetrahedra, and an edgeedge with one CuO4 tetrahedra. There are a spread of Na–O bond distances ranging from 2.36–2.51 Å. In the fourth Na1+ site, Na1+ is bonded to four O2- atoms to form distorted NaO4 tetrahedra that share corners with two equivalent CuO4 tetrahedra, corners with five NaO4 tetrahedra, and an edgeedge with one CuO4 tetrahedra. There are a spread of Na–O bond distances ranging from 2.29–2.42 Å. In the fifth Na1+ site, Na1+ is bonded in a 4-coordinate geometry to six O2- atoms. There are a spread of Na–O bond distances ranging from 2.39–2.99 Å. Cu3+ is bonded to four O2- atoms to form CuO4 tetrahedra that share corners with four NaO4 tetrahedra and edges with two NaO4 tetrahedra. There are a spread of Cu–O bond distances ranging from 1.90–1.94 Å. There are four inequivalent O2- sites. In the first O2- site, O2- is bonded in a 6-coordinate geometry to six Na1+ and one Cu3+ atom. In the second O2- site, O2- is bonded to five Na1+ and one Cu3+ atom to form a mixture of distorted edge and corner-sharing ONa5Cu octahedra. The corner-sharing octahedra tilt angles range from 52–73°. In the third O2- site, O2- is bonded in a 7-coordinate geometry to six Na1+ and one Cu3+ atom. In the fourth O2- site, O2- is bonded to five Na1+ and one Cu3+ atom to form a mixture of distorted edge and corner-sharing ONa5Cu octahedra. The corner-sharing octahedra tilt angles range from 52–71°.