Cobalt(II) and nickel(II) coordination polymers constructed from P,P′-diphenylmethylenediphosphinic acid (H2pcp) and 4,4′-bipyridine (bipy): Structural isomerism in [Co(pcp)(bipy)0.5(H2O)2]

Two polymeric structural isomers of formula [Co(pcp)(bipy)0.5(H2O)2] are reported, the one showing an undulated 2D-layered structure, the other an infinite mono-dimensional strand arrangement. Both the frameworks extend their dimensionality through hydrogen bonding interactions. An unique species of [Ni(pcp)(bipy)0.5(H2O)2], isomorphous with the 2D cobalt isomer, was obtained.