Materials Data on NaP(HO2)2 by Materials Project

Abstract

NaH2PO4 crystallizes in the monoclinic P2_1/c space group. The structure is three-dimensional. there are two inequivalent Na1+ sites. In the first Na1+ site, Na1+ is bonded to six O2- atoms to form distorted NaO6 octahedra that share corners with four PO4 tetrahedra, an edgeedge with one NaO6 octahedra, and an edgeedge with one PO4 tetrahedra. There are a spread of Na–O bond distances ranging from 2.32–2.71 Å. In the second Na1+ site, Na1+ is bonded in a 7-coordinate geometry to one H1+ and six O2- atoms. The Na–H bond length is 2.48 Å. There are a spread of Na–O bond distances ranging from 2.35–2.63 Å. There are two inequivalent P5+ sites. In the first P5+ site, P5+ is bonded to four O2- atoms to form PO4 tetrahedra that share corners with three equivalent NaO6 octahedra and corners with two equivalent PO4 tetrahedra. The corner-sharing octahedra tilt angles range from 49–58°. There are a spread of P–O bond distances ranging from 1.49–1.64 Å. In the second P5+ site, P5+ is bonded to four O2- atoms to form PO4 tetrahedra that share a cornercorner with one NaO6 octahedra, corners with two equivalent PO4 tetrahedra, and an edgeedge with one NaO6 octahedra. The corner-sharing octahedral tilt angles are 58°. There are a spread of P–O bond distances ranging from 1.50–1.63 Å. There are four 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 0.98 Å. In the second 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 third 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 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. There are eight inequivalent O2- sites. In the first O2- site, O2- is bonded in a 2-coordinate geometry to one Na1+ and two P5+ atoms. In the second O2- site, O2- is bonded in a bent 120 degrees geometry to two P5+ atoms. In the third O2- site, O2- is bonded in a 3-coordinate geometry to two equivalent Na1+ and one P5+ atom. In the fourth O2- site, O2- is bonded in a 3-coordinate geometry to two equivalent Na1+ and one P5+ atom. In the fifth O2- site, O2- is bonded in a distorted water-like geometry to two Na1+ and two H1+ atoms. In the sixth O2- site, O2- is bonded in a distorted single-bond geometry to two Na1+ and one P5+ atom. In the seventh O2- site, O2- is bonded in a bent 120 degrees geometry to one Na1+ and one P5+ atom. In the eighth O2- site, O2- is bonded in a distorted water-like geometry to two equivalent Na1+ and two H1+ atoms.