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metal-organic compounds
The cation in the title compound, Na+.C4H12NO7P2-.3H2O, has the expected zwitterionic character, with a terminal protonated amine group on one side of the chain and a negatively charged diphosphonate group on the other, the latter interacting with the Na+ ion. The structure is stabilized by a complex hydrogen-bonding scheme, which is found to be weaker than that observed in the free acid.