Materials Data on NaH5S2O9 by Materials Project
(NaH4(SO3)2)2H2O2(O2)2 crystallizes in the monoclinic P2_1/c space group. The structure is two-dimensional and consists of two hydrogen peroxide molecules; four water molecules; four water molecules; and one NaH4(SO3)2 sheet oriented in the (1, 0, 0) direction. In the NaH4(SO3)2 sheet, Na1+ is bonded in a rectangular see-saw-like geometry to four O2- atoms. There are a spread of Na–O bond distances ranging from 2.26–2.48 Å. There are four inequivalent H1+ sites. In the first H1+ site, H1+ is bonded in a single-bond geometry to one S6+ atom. The H–S bond length is 1.40 Å. In the second H1+ site, H1+ is bonded in a single-bond geometry to one O2- atom. The H–O bond length is 1.00 Å. In the third H1+ site, H1+ is bonded in a linear geometry to two O2- atoms. There is one shorter (1.04 Å) and one longer (1.56 Å) H–O bond length. In the fourth H1+ site, H1+ is bonded in a single-bond geometry to one O2- atom. The H–O bond length is 1.00 Å. There are two inequivalent S6+ sites. In the first S6+ site, S6+ is bonded in a trigonal non-coplanar geometry to one H1+ and two O2- atoms. There is one shorter (1.50 Å) and one longer (1.53 Å) S–O bond length. In the second S6+ site, S6+ is bonded in a trigonal non-coplanar geometry to three O2- atoms. There are a spread of S–O bond distances ranging from 1.47–1.64 Å. There are six inequivalent O2- sites. In the first O2- site, O2- is bonded in a distorted bent 150 degrees geometry to one Na1+ and one S6+ atom. In the second O2- site, O2- is bonded in a distorted trigonal non-coplanar geometry to one Na1+, one H1+, and one S6+ atom. In the third O2- site, O2- is bonded in a single-bond geometry to one H1+ atom. In the fourth O2- site, O2- is bonded in a water-like geometry to one H1+ and one S6+ atom. In the fifth O2- site, O2- is bonded in a linear geometry to one Na1+ and one S6+ atom. In the sixth O2- site, O2- is bonded in a 1-coordinate geometry to one Na1+, one H1+, and one S6+ atom.