Materials Data on Na4P2H20O17 by Materials Project
(Na2PH7O8)2(H2)2H2O crystallizes in the monoclinic C2/c space group. The structure is one-dimensional and consists of eight hydrogen molecules; four water molecules; and eight Na2PH7O8 ribbons oriented in the (0, 1, 0) direction. In each Na2PH7O8 ribbon, there are two inequivalent Na1+ sites. In the first Na1+ site, Na1+ is bonded in a 4-coordinate geometry to four O2- atoms. There are a spread of Na–O bond distances ranging from 2.26–2.60 Å. In the second Na1+ site, Na1+ is bonded in a 1-coordinate geometry to one H1+ and three O2- atoms. The Na–H bond length is 2.27 Å. There are a spread of Na–O bond distances ranging from 2.23–2.39 Å. P5+ is bonded in a tetrahedral geometry to four O2- atoms. There are a spread of P–O bond distances ranging from 1.49–1.62 Å. There are seven inequivalent H1+ sites. In the first 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 second H1+ site, H1+ is bonded in a single-bond geometry to one O2- atom. The H–O bond length is 1.02 Å. In the third H1+ site, H1+ is bonded in a linear geometry to two O2- atoms. There is one shorter (1.15 Å) and one longer (1.26 Å) H–O bond length. In the fourth H1+ site, H1+ is bonded in a single-bond geometry to one Na1+ and one O2- atom. The H–O bond length is 0.99 Å. In the fifth H1+ site, H1+ is bonded in a single-bond geometry to one O2- atom. The H–O bond length is 0.98 Å. In the sixth H1+ site, H1+ is bonded in a single-bond geometry to one O2- atom. The H–O bond length is 0.97 Å. In the seventh H1+ site, H1+ is bonded in a single-bond geometry to one O2- atom. The H–O bond length is 0.99 Å. There are eight inequivalent O2- sites. In the first O2- site, O2- is bonded in a distorted bent 120 degrees geometry to one Na1+ and one P5+ atom. In the second O2- site, O2- is bonded in a 1-coordinate geometry to two Na1+ and one O2- atom. The O–O bond length is 1.49 Å. In the third O2- site, O2- is bonded in a distorted water-like geometry to one P5+ and one H1+ atom. In the fourth O2- site, O2- is bonded in a water-like geometry to one Na1+ and two H1+ atoms. In the fifth O2- site, O2- is bonded in a bent 120 degrees geometry to one P5+ and one H1+ atom. In the sixth O2- site, O2- is bonded in a distorted single-bond geometry to two Na1+ and one H1+ atom. In the seventh O2- site, O2- is bonded in a 2-coordinate geometry to one Na1+, one P5+, and one H1+ atom. In the eighth O2- site, O2- is bonded in a distorted bent 120 degrees geometry to two H1+ and one O2- atom.