DOI: 10.17188/1679562
title: Materials Data on NiP2H2O7 by Materials Project

description: NiP2H2O7 crystallizes in the monoclinic P2_1/c space group. The structure is three-dimensional. there are two inequivalent Ni2+ sites. In the first Ni2+ site, Ni2+ is bonded to six O2- atoms to form NiO6 octahedra that share corners with six PO4 tetrahedra and edges with two equivalent NiO6 octahedra. There are a spread of Ni–O bond distances ranging from 2.05–2.13 Å. In the second Ni2+ site, Ni2+ is bonded to six O2- atoms to form NiO6 octahedra that share corners with six PO4 tetrahedra and edges with two equivalent NiO6 octahedra. There are a spread of Ni–O bond distances ranging from 1.98–2.14 Å. There are four inequivalent P5+ sites. In the first P5+ site, P5+ is bonded to four O2- atoms to form PO4 tetrahedra that share corners with three NiO6 octahedra and a cornercorner with one PO4 tetrahedra. The corner-sharing octahedra tilt angles range from 52–55°. There are a spread of P–O bond distances ranging from 1.51–1.58 Å. In the second P5+ site, P5+ is bonded to four O2- atoms to form PO4 tetrahedra that share corners with three NiO6 octahedra and a cornercorner with one PO4 tetrahedra. The corner-sharing octahedra tilt angles range from 36–52°. There are a spread of P–O bond distances ranging from 1.49–1.61 Å. In the third P5+ site, P5+ is bonded to four O2- atoms to form PO4 tetrahedra that share corners with three NiO6 octahedra and a cornercorner with one PO4 tetrahedra. The corner-sharing octahedra tilt angles range from 52–57°. There are a spread of P–O bond distances ranging from 1.52–1.59 Å. In the fourth P5+ site, P5+ is bonded to four O2- atoms to form PO4 tetrahedra that share corners with three NiO6 octahedra and a cornercorner with one PO4 tetrahedra. The corner-sharing octahedra tilt angles range from 41–50°. There are a spread of P–O bond distances ranging from 1.51–1.62 Å. There are four inequivalent H1+ sites. In the first H1+ site, H1+ is bonded in a single-bond geometry to two O2- atoms. There is one shorter (1.01 Å) and one longer (1.73 Å) H–O bond length. In the second H1+ site, H1+ is bonded in a single-bond geometry to two O2- atoms. There is one shorter (1.01 Å) and one longer (1.72 Å) H–O bond length. 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 O2- atom. The H–O bond length is 0.99 Å. There are fourteen inequivalent O2- sites. In the first O2- site, O2- is bonded in a 3-coordinate geometry to two Ni2+ and one P5+ atom. In the second O2- site, O2- is bonded in a distorted trigonal planar geometry to two Ni2+ and one P5+ atom. In the third O2- site, O2- is bonded in a 3-coordinate geometry to one Ni2+, one P5+, and one H1+ atom. In the fourth O2- site, O2- is bonded in a 3-coordinate geometry to one Ni2+, one P5+, and one H1+ atom. In the fifth O2- site, O2- is bonded in a distorted trigonal planar geometry to two Ni2+ and one P5+ atom. In the sixth O2- site, O2- is bonded in a bent 150 degrees geometry to two P5+ atoms. In the seventh O2- site, O2- is bonded in a bent 120 degrees geometry to one P5+ and one H1+ atom. In the eighth O2- site, O2- is bonded in a bent 120 degrees geometry to one P5+ and one H1+ atom. In the ninth O2- site, O2- is bonded in a distorted trigonal planar geometry to two Ni2+ and one P5+ atom. In the tenth O2- site, O2- is bonded in a distorted bent 150 degrees geometry to one Ni2+ and one P5+ atom. In the eleventh O2- site, O2- is bonded in a bent 150 degrees geometry to two P5+ atoms. In the twelfth O2- site, O2- is bonded in a bent 150 degrees geometry to one Ni2+ and one P5+ atom. In the thirteenth O2- site, O2- is bonded in a bent 120 degrees geometry to one P5+ and one H1+ atom. In the fourteenth O2- site, O2- is bonded in a bent 120 degrees geometry to one P5+ and one H1+ atom.