Materials Data on Na4C2O5 by Materials Project
Na4C2O5 crystallizes in the monoclinic Cm space group. The structure is three-dimensional. there are four inequivalent Na1+ sites. In the first Na1+ site, Na1+ is bonded to five O2- atoms to form a mixture of edge and face-sharing NaO5 square pyramids. There are a spread of Na–O bond distances ranging from 2.27–2.40 Å. In the second Na1+ site, Na1+ is bonded in a 8-coordinate geometry to eight O2- atoms. There are a spread of Na–O bond distances ranging from 2.51–2.98 Å. In the third Na1+ site, Na1+ is bonded in a 5-coordinate geometry to seven O2- atoms. There are a spread of Na–O bond distances ranging from 2.49–2.97 Å. In the fourth Na1+ site, Na1+ is bonded to five O2- atoms to form a mixture of distorted edge and face-sharing NaO5 square pyramids. There are a spread of Na–O bond distances ranging from 2.30–2.52 Å. There are two inequivalent C3+ sites. In the first C3+ site, C3+ is bonded in a bent 120 degrees geometry to two equivalent O2- atoms. Both C–O bond lengths are 1.31 Å. In the second C3+ site, C3+ is bonded in a trigonal planar geometry to three O2- atoms. There is one shorter (1.29 Å) and two longer (1.30 Å) C–O bond length. There are three inequivalent O2- sites. In the first O2- site, O2- is bonded in a 1-coordinate geometry to five Na1+ and one C3+ atom. In the second O2- site, O2- is bonded in a 1-coordinate geometry to five Na1+ and one C3+ atom. In the third O2- site, O2- is bonded in a 1-coordinate geometry to five Na1+ and one C3+ atom.