Materials Data on P(HO)3 by Materials Project

H3PO3 crystallizes in the monoclinic P2_1 space group. The structure is one-dimensional and consists of four phosphorous acid molecules and two H3PO3 ribbons oriented in the (0, 1, 0) direction. In each H3PO3 ribbon, P5+ is bonded in a trigonal non-coplanar geometry to three O2- atoms. There is one shorter (1.61 Å) and two longer (1.64 Å) P–O bond length. There are three inequivalent H+0.33+ sites. In the first H+0.33+ site, H+0.33+ is bonded in a single-bond geometry to one O2- atom. The H–O bond length is 1.00 Å. In the second H+0.33+ site, H+0.33+ is bonded in a distorted single-bond geometry to two O2- atoms. There is one shorter (1.00 Å) and one longer (1.70 Å) H–O bond length. In the third H+0.33+ site, H+0.33+ is bonded in a single-bond geometry to one O2- atom. The H–O bond length is 1.01 Å. There are three inequivalent O2- sites. In the first O2- site, O2- is bonded in a distorted bent 120 degrees geometry to one P5+ and one H+0.33+ atom. In the second O2- site, O2- is bonded in a bent 120 degrees geometry to one P5+ and one H+0.33+ atom. In the third O2- site, O2- is bonded in a distorted trigonal planar geometry to one P5+ and two H+0.33+ atoms.