DOI: 10.17188/1687562
title: Materials Data on RbNi4(PO4)3 by Materials Project

description: RbNi4(PO4)3 crystallizes in the orthorhombic Pnnm space group. The structure is three-dimensional. Rb1+ is bonded in a 6-coordinate geometry to eight O2- atoms. There are a spread of Rb–O bond distances ranging from 2.80–3.19 Å. There are three inequivalent Ni2+ sites. In the first Ni2+ site, Ni2+ is bonded to five O2- atoms to form NiO5 trigonal bipyramids that share corners with two equivalent NiO6 octahedra, corners with five PO4 tetrahedra, and an edgeedge with one NiO5 trigonal bipyramid. The corner-sharing octahedral tilt angles are 59°. There are a spread of Ni–O bond distances ranging from 1.98–2.11 Å. In the second Ni2+ site, Ni2+ is bonded to six O2- atoms to form NiO6 octahedra that share corners with two equivalent NiO6 octahedra, corners with four PO4 tetrahedra, edges with two equivalent NiO6 octahedra, and an edgeedge with one PO4 tetrahedra. The corner-sharing octahedral tilt angles are 66°. There are a spread of Ni–O bond distances ranging from 1.99–2.22 Å. In the third Ni2+ site, Ni2+ is bonded to six O2- atoms to form NiO6 octahedra that share a cornercorner with one NiO6 octahedra, corners with four PO4 tetrahedra, a cornercorner with one NiO5 trigonal bipyramid, edges with three NiO6 octahedra, and an edgeedge with one PO4 tetrahedra. The corner-sharing octahedral tilt angles are 66°. There are a spread of Ni–O bond distances ranging from 2.04–2.33 Å. There are three inequivalent P5+ sites. In the first P5+ site, P5+ is bonded to four O2- atoms to form PO4 tetrahedra that share corners with five NiO6 octahedra and corners with two equivalent NiO5 trigonal bipyramids. The corner-sharing octahedra tilt angles range from 51–60°. There are a spread of P–O bond distances ranging from 1.52–1.63 Å. In the second P5+ site, P5+ is bonded to four O2- atoms to form PO4 tetrahedra that share corners with four NiO6 octahedra, a cornercorner with one NiO5 trigonal bipyramid, and edges with two equivalent NiO6 octahedra. The corner-sharing octahedra tilt angles range from 47–52°. There is three shorter (1.55 Å) and one longer (1.60 Å) P–O bond length. In the third P5+ site, P5+ is bonded to four O2- atoms to form PO4 tetrahedra that share corners with three NiO6 octahedra, corners with two equivalent NiO5 trigonal bipyramids, and an edgeedge with one NiO6 octahedra. The corner-sharing octahedra tilt angles range from 8–59°. There are a spread of P–O bond distances ranging from 1.52–1.58 Å. There are nine inequivalent O2- sites. In the first O2- site, O2- is bonded in a distorted trigonal planar geometry to two equivalent Ni2+ and one P5+ atom. In the second O2- site, O2- is bonded in a distorted trigonal planar geometry to two equivalent Ni2+ and one P5+ atom. In the third O2- site, O2- is bonded in a 1-coordinate geometry to one Rb1+, two Ni2+, and one P5+ atom. In the fourth O2- site, O2- is bonded in a 2-coordinate geometry to one Rb1+, one Ni2+, and one P5+ atom. In the fifth O2- site, O2- is bonded in a 3-coordinate geometry to two equivalent Ni2+ and one P5+ atom. In the sixth O2- site, O2- is bonded in a 4-coordinate geometry to one Rb1+, two Ni2+, and one P5+ atom. In the seventh O2- site, O2- is bonded in a 4-coordinate geometry to three Ni2+ and one P5+ atom. In the eighth O2- site, O2- is bonded in a rectangular see-saw-like geometry to three Ni2+ and one P5+ atom. In the ninth O2- site, O2- is bonded in a distorted linear geometry to two equivalent Rb1+, one Ni2+, and one P5+ atom.