Hydronium (cyclo­heptyl­ammonio)­methyl­ene‐1,1‐bis­phospho­nate (hydronium incadronate)

The structure of the title compound, H₃O⁺·C₈H₁₈NO₆P₂⁻, adopts a zwitterionic form containing an alkyl­ammonium group, a hydro­nium ion, and two negatively charged phosphon­ate groups. The cyclo­heptyl side chain adopts a twist‐chair conformation. The crystal packing is dominated by an extensive hydrogen‐bonding network.