DOI: 10.17188/1717598
title: Materials Data on NaNi4(P2O11)2 by Materials Project

description: NaNi4(PO5)4O2 crystallizes in the monoclinic P2_1 space group. The structure is three-dimensional and consists of two oxygen molecules and one NaNi4(PO5)4 framework. In the NaNi4(PO5)4 framework, Na is bonded in a 6-coordinate geometry to six O atoms. There are a spread of Na–O bond distances ranging from 2.29–2.99 Å. There are four inequivalent Ni sites. In the first Ni site, Ni is bonded to five O atoms to form NiO5 trigonal bipyramids that share corners with two NiO5 square pyramids, corners with four PO4 tetrahedra, and an edgeedge with one NiO5 square pyramid. There are a spread of Ni–O bond distances ranging from 1.92–2.06 Å. In the second Ni site, Ni is bonded to five O atoms to form NiO5 square pyramids that share a cornercorner with one NiO5 square pyramid, corners with four PO4 tetrahedra, a cornercorner with one NiO5 trigonal bipyramid, and an edgeedge with one NiO5 square pyramid. There are a spread of Ni–O bond distances ranging from 1.91–2.05 Å. In the third Ni site, Ni is bonded to five O atoms to form NiO5 square pyramids that share corners with two NiO5 square pyramids, corners with four PO4 tetrahedra, and an edgeedge with one NiO5 trigonal bipyramid. There are a spread of Ni–O bond distances ranging from 1.90–2.04 Å. In the fourth Ni site, Ni is bonded to five O atoms to form NiO5 square pyramids that share a cornercorner with one NiO5 square pyramid, corners with four PO4 tetrahedra, a cornercorner with one NiO5 trigonal bipyramid, and an edgeedge with one NiO5 square pyramid. There are a spread of Ni–O bond distances ranging from 1.88–2.04 Å. There are four inequivalent P sites. In the first P site, P is bonded to four O atoms to form PO4 tetrahedra that share corners with three NiO5 square pyramids and a cornercorner with one NiO5 trigonal bipyramid. There are a spread of P–O bond distances ranging from 1.53–1.58 Å. In the second P site, P is bonded to four O atoms to form PO4 tetrahedra that share corners with three NiO5 square pyramids and a cornercorner with one NiO5 trigonal bipyramid. There is two shorter (1.54 Å) and two longer (1.56 Å) P–O bond length. In the third P site, P is bonded to four O atoms to form PO4 tetrahedra that share corners with three NiO5 square pyramids and a cornercorner with one NiO5 trigonal bipyramid. There are a spread of P–O bond distances ranging from 1.53–1.57 Å. In the fourth P site, P is bonded to four O atoms to form PO4 tetrahedra that share corners with three NiO5 square pyramids and a cornercorner with one NiO5 trigonal bipyramid. There are a spread of P–O bond distances ranging from 1.53–1.60 Å. There are twenty inequivalent O sites. In the first O site, O is bonded in a distorted bent 120 degrees geometry to one Ni and one P atom. In the second O site, O is bonded in a 3-coordinate geometry to one Na, one Ni, and one P atom. In the third O site, O is bonded in a distorted trigonal planar geometry to two Ni and one P atom. In the fourth O site, O is bonded in a distorted trigonal planar geometry to two Ni and one P atom. In the fifth O site, O is bonded in a single-bond geometry to one P atom. In the sixth O site, O is bonded in a bent 120 degrees geometry to two Ni atoms. In the seventh O site, O is bonded in a bent 120 degrees geometry to two Ni atoms. In the eighth O site, O is bonded in a bent 120 degrees geometry to one Na and one P atom. In the ninth O site, O is bonded in a water-like geometry to one Na and one P atom. In the tenth O site, O is bonded in a trigonal planar geometry to two Ni and one P atom. In the eleventh O site, O is bonded in a trigonal planar geometry to two Ni and one P atom. In the twelfth O site, O is bonded in a single-bond geometry to one O atom. The O–O bond length is 1.23 Å. In the thirteenth O site, O is bonded in a distorted L-shaped geometry to one Na and one P atom. In the fourteenth O site, O is bonded in a bent 120 degrees geometry to one Na and one O atom. In the fifteenth O site, O is bonded in a single-bond geometry to one P atom. In the sixteenth O site, O is bonded in a distorted water-like geometry to one Na and one P atom. In the seventeenth O site, O is bonded in a distorted trigonal planar geometry to two Ni and one P atom. In the eighteenth O site, O is bonded in a distorted bent 150 degrees geometry to one Ni and one P atom. In the nineteenth O site, O is bonded in a distorted trigonal planar geometry to two Ni and one P atom. In the twentieth O site, O is bonded in a distorted bent 150 degrees geometry to one Ni and one P atom.