Materials Data on CaNi2O5 by Materials Project
CaNi2O5 crystallizes in the monoclinic Pm space group. The structure is three-dimensional. there are two inequivalent Ca2+ sites. In the first Ca2+ site, Ca2+ is bonded in a 8-coordinate geometry to eight O2- atoms. There are a spread of Ca–O bond distances ranging from 2.27–2.51 Å. In the second Ca2+ site, Ca2+ is bonded in a 8-coordinate geometry to eight O2- atoms. There are a spread of Ca–O bond distances ranging from 2.28–2.53 Å. There are four inequivalent Ni4+ sites. In the first Ni4+ site, Ni4+ is bonded to five O2- atoms to form a mixture of edge and corner-sharing NiO5 trigonal bipyramids. There are a spread of Ni–O bond distances ranging from 1.84–2.02 Å. In the second Ni4+ site, Ni4+ is bonded to five O2- atoms to form a mixture of edge and corner-sharing NiO5 trigonal bipyramids. There are a spread of Ni–O bond distances ranging from 1.84–2.02 Å. In the third Ni4+ site, Ni4+ is bonded to five O2- atoms to form a mixture of edge and corner-sharing NiO5 trigonal bipyramids. There are a spread of Ni–O bond distances ranging from 1.83–2.01 Å. In the fourth Ni4+ site, Ni4+ is bonded to five O2- atoms to form a mixture of edge and corner-sharing NiO5 trigonal bipyramids. There are a spread of Ni–O bond distances ranging from 1.83–2.01 Å. There are ten inequivalent O2- sites. In the first O2- site, O2- is bonded to two equivalent Ca2+ and two Ni4+ atoms to form corner-sharing OCa2Ni2 tetrahedra. In the second O2- site, O2- is bonded to two equivalent Ca2+ and two Ni4+ atoms to form corner-sharing OCa2Ni2 tetrahedra. In the third O2- site, O2- is bonded in a 4-coordinate geometry to one Ca2+ and three Ni4+ atoms. In the fourth O2- site, O2- is bonded in a 4-coordinate geometry to one Ca2+ and three Ni4+ atoms. In the fifth O2- site, O2- is bonded in a 4-coordinate geometry to one Ca2+ and three Ni4+ atoms. In the sixth O2- site, O2- is bonded in a 4-coordinate geometry to one Ca2+ and three Ni4+ atoms. In the seventh O2- site, O2- is bonded in a 1-coordinate geometry to two equivalent Ca2+, one Ni4+, and one O2- atom. The O–O bond length is 1.45 Å. In the eighth O2- site, O2- is bonded in a 1-coordinate geometry to two equivalent Ca2+, one Ni4+, and one O2- atom. The O–O bond length is 1.46 Å. In the ninth O2- site, O2- is bonded in a 1-coordinate geometry to two equivalent Ca2+, one Ni4+, and one O2- atom. In the tenth O2- site, O2- is bonded in a 1-coordinate geometry to two equivalent Ca2+, one Ni4+, and one O2- atom.