Materials Data on CaNiP2O7 by Materials Project

Abstract

CaNiP2O7 crystallizes in the triclinic P-1 space group. The structure is three-dimensional. Ca2+ is bonded in a 7-coordinate geometry to seven O2- atoms. There are a spread of Ca–O bond distances ranging from 2.29–2.71 Å. Ni2+ is bonded to six O2- atoms to form NiO6 octahedra that share corners with six PO4 tetrahedra and an edgeedge with one NiO6 octahedra. There are a spread of Ni–O bond distances ranging from 2.09–2.19 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 NiO6 octahedra and a cornercorner with one PO4 tetrahedra. The corner-sharing octahedra tilt angles range from 44–60°. There are a spread of P–O bond distances ranging from 1.51–1.59 Å. In the second P5+ site, P5+ is bonded to four O2- atoms to form PO4 tetrahedra that share corners with three equivalent NiO6 octahedra and a cornercorner with one PO4 tetrahedra. The corner-sharing octahedra tilt angles range from 42–55°. There are a spread of P–O bond distances ranging from 1.52–1.63 Å. There are seven inequivalent O2- sites. In the first O2- site, O2- is bonded in a distorted bent 150 degrees geometry to two P5+ atoms. In the second O2- site, O2- is bonded in a 3-coordinate geometry to one Ca2+, one Ni2+, and one P5+ atom. In the third O2- site, O2- is bonded in a distorted trigonal planar geometry to one Ca2+, one Ni2+, and one P5+ atom. In the fourth O2- site, O2- is bonded in a 3-coordinate geometry to one Ca2+, one Ni2+, and one P5+ atom. In the fifth O2- site, O2- is bonded in a 3-coordinate geometry to two equivalent Ca2+ and one P5+ atom. In the sixth O2- site, O2- is bonded in a 1-coordinate geometry to one Ca2+, two equivalent Ni2+, and one P5+ atom. In the seventh O2- site, O2- is bonded in a 1-coordinate geometry to one Ca2+, one Ni2+, and one P5+ atom.