DOI: 10.17188/1714554
title: Materials Data on NaNi4(PO4)3 by Materials Project

description: NaNi4(PO4)3 crystallizes in the orthorhombic Cmc2_1 space group. The structure is three-dimensional. Na1+ is bonded in a 6-coordinate geometry to six O2- atoms. There are a spread of Na–O bond distances ranging from 2.40–2.70 Å. There are three inequivalent Ni2+ sites. In the first Ni2+ site, Ni2+ is bonded to six O2- atoms to form distorted NiO6 octahedra that share corners with two equivalent NiO6 octahedra, corners with four equivalent NiO5 square pyramids, corners with two equivalent PO4 tetrahedra, and edges with two PO4 tetrahedra. The corner-sharing octahedra tilt angles range from 29–45°. There are a spread of Ni–O bond distances ranging from 1.97–2.38 Å. In the second Ni2+ site, Ni2+ is bonded to six O2- atoms to form distorted NiO6 octahedra that share corners with two equivalent NiO6 octahedra, corners with four equivalent NiO5 square pyramids, corners with four PO4 tetrahedra, and an edgeedge with one PO4 tetrahedra. The corner-sharing octahedra tilt angles range from 29–45°. There are a spread of Ni–O bond distances ranging from 1.98–2.45 Å. In the third Ni2+ site, Ni2+ is bonded to five O2- atoms to form NiO5 square pyramids that share corners with four NiO6 octahedra, corners with five PO4 tetrahedra, and edges with two equivalent NiO5 square pyramids. The corner-sharing octahedra tilt angles range from 65–75°. There are a spread of Ni–O bond distances ranging from 1.96–2.11 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 two equivalent NiO6 octahedra, corners with four equivalent NiO5 square pyramids, and an edgeedge with one NiO6 octahedra. The corner-sharing octahedral tilt angles are 35°. There are a spread of P–O bond distances ranging from 1.51–1.61 Å. In the second P5+ site, P5+ is bonded to four O2- atoms to form PO4 tetrahedra that share corners with two equivalent NiO6 octahedra, corners with four equivalent NiO5 square pyramids, and an edgeedge with one NiO6 octahedra. The corner-sharing octahedral tilt angles are 34°. There are a spread of P–O bond distances ranging from 1.51–1.61 Å. In the third P5+ site, P5+ is bonded to four O2- atoms to form PO4 tetrahedra that share corners with two equivalent NiO6 octahedra, corners with two equivalent NiO5 square pyramids, and an edgeedge with one NiO6 octahedra. The corner-sharing octahedra tilt angles range from 50–64°. There is two shorter (1.55 Å) and two longer (1.56 Å) P–O bond length. There are nine inequivalent O2- sites. In the first O2- site, O2- is bonded in a 4-coordinate geometry to three Ni2+ and one P5+ atom. In the second O2- site, O2- is bonded in a 4-coordinate geometry to three Ni2+ and one P5+ atom. In the third O2- site, O2- is bonded to three Ni2+ and one P5+ atom to form distorted edge-sharing ONi3P tetrahedra. In the fourth O2- site, O2- is bonded to three Ni2+ and one P5+ atom to form distorted edge-sharing ONi3P tetrahedra. In the fifth O2- site, O2- is bonded in a distorted trigonal planar geometry to one Na1+, one Ni2+, and one P5+ atom. In the sixth O2- site, O2- is bonded in a 3-coordinate geometry to two Ni2+ and one P5+ atom. In the seventh O2- site, O2- is bonded in a 2-coordinate geometry to one Na1+, one Ni2+, and one P5+ atom. In the eighth O2- site, O2- is bonded in a 2-coordinate geometry to one Na1+, one Ni2+, and one P5+ atom. In the ninth O2- site, O2- is bonded in a 3-coordinate geometry to two Ni2+ and one P5+ atom.