DOE OSTI2020
Na2S2O3 crystallizes in the orthorhombic Pna2_1 space group. The structure is three-dimensional and consists of twelve hydrogen sulfide molecules and one Na2SO3 framework. In the Na2SO3 framework, there are six inequivalent Na1+ sites. In the first Na1+ site, Na1+ is bonded to five O2- atoms to form distorted corner-sharing NaO5 square pyramids. There are a spread of Na–O bond distances ranging from 2.41–2.60 Å. In the second Na1+ site, Na1+ is bonded to four O2- atoms to form corner-sharing NaO4 tetrahedra. There are a spread of Na–O bond distances ranging from 2.29–2.40 Å. In the third 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 2.38–2.52 Å. In the fourth Na1+ site, Na1+ is bonded in a 6-coordinate geometry to six O2- atoms. There are a spread of Na–O bond distances ranging from 2.36–2.94 Å. In the fifth Na1+ site, Na1+ is bonded in a 3-coordinate geometry to three O2- atoms. There are a spread of Na–O bond distances ranging from 2.37–2.72 Å. In the sixth Na1+ site, Na1+ is bonded in a T-shaped geometry to three O2- atoms. There are a spread of Na–O bond distances ranging from 2.32–2.43 Å. There are three inequivalent S2+ sites. In the first S2+ site, S2+ is bonded in a trigonal non-coplanar geometry to three O2- atoms. There is one shorter (1.48 Å) and two longer (1.50 Å) S–O bond length. In the second S2+ site, S2+ is bonded in a trigonal non-coplanar geometry to three O2- atoms. There are a spread of S–O bond distances ranging from 1.48–1.51 Å. In the third S2+ site, S2+ is bonded in a trigonal non-coplanar geometry to three O2- atoms. All S–O bond lengths are 1.49 Å. There are nine inequivalent O2- sites. In the first O2- site, O2- is bonded in a 4-coordinate geometry to three Na1+ and one S2+ atom. In the second O2- site, O2- is bonded in a 4-coordinate geometry to three Na1+ and one S2+ atom. In the third O2- site, O2- is bonded in a trigonal planar geometry to two Na1+ and one S2+ atom. In the fourth O2- site, O2- is bonded in a 4-coordinate geometry to three Na1+ and one S2+ atom. In the fifth O2- site, O2- is bonded in a 3-coordinate geometry to two Na1+ and one S2+ atom. In the sixth O2- site, O2- is bonded to three Na1+ and one S2+ atom to form distorted corner-sharing ONa3S tetrahedra. In the seventh O2- site, O2- is bonded to three Na1+ and one S2+ atom to form distorted corner-sharing ONa3S tetrahedra. In the eighth O2- site, O2- is bonded in a 2-coordinate geometry to three Na1+ and one S2+ atom. In the ninth O2- site, O2- is bonded in a distorted see-saw-like geometry to three Na1+ and one S2+ atom.