The O 2px and 2py components are nonbonding, whereas the O 2pz orbitals overlap under the influence of significant Cu(dxz,yzu03c0*)u2212O(pzu03c0) antibonding hybridization to form spatially delocalized O(pzu03c0)u2212O(pzu03c0) bonding molecular orbitals parallel to the Cuu2013O x u2212...