Poly[piperazinium(2+) [hexa-mu-hydrogen phosphito-mu-piperazine-pentazinc(II)]]

The title compound, {(C4H12N2)[Zn-5(HPO3)(6)(C4H10N2)]}(n) contains ZnO4, ZnO3N and HPO3 polyhedral building units linked by Zn - O - P bridges (mean Zn - O - P = 133.6 degrees). The organic species exists in two forms, i.e. as neutral molecules that bond directly to zinc as ligands via both N atoms and as diprotonated cations that interact with the framework by way of N-H center dot center dot center dot O hydrogen bonds. Both organic components lie across centres of inversion.