Materials Data on Na4MgO3 by Materials Project
Na4MgO3 crystallizes in the monoclinic Cc space group. The structure is three-dimensional. there are four inequivalent Na1+ sites. In the first Na1+ site, Na1+ is bonded to four O2- atoms to form a mixture of distorted edge and corner-sharing NaO4 trigonal pyramids. There are a spread of Na–O bond distances ranging from 2.36–2.65 Å. In the second Na1+ site, Na1+ is bonded to four O2- atoms to form a mixture of distorted edge and corner-sharing NaO4 trigonal pyramids. There are a spread of Na–O bond distances ranging from 2.31–2.63 Å. In the third Na1+ site, Na1+ is bonded in a trigonal planar geometry to three O2- atoms. There are a spread of Na–O bond distances ranging from 2.22–2.30 Å. In the fourth Na1+ site, Na1+ is bonded to four O2- atoms to form a mixture of distorted edge and corner-sharing NaO4 trigonal pyramids. There are a spread of Na–O bond distances ranging from 2.34–2.44 Å. Mg2+ is bonded in a trigonal planar geometry to three O2- atoms. There is one shorter (1.93 Å) and two longer (1.94 Å) Mg–O bond length. There are three inequivalent O2- sites. In the first O2- site, O2- is bonded to five Na1+ and one Mg2+ atom to form corner-sharing ONa5Mg octahedra. The corner-sharing octahedral tilt angles are 66°. In the second O2- site, O2- is bonded in a 6-coordinate geometry to five Na1+ and one Mg2+ atom. In the third O2- site, O2- is bonded in a 6-coordinate geometry to five Na1+ and one Mg2+ atom.