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organic compounds
The molecular structures of the title compounds, C11H11N4O+.I− and C13H15N4O+.I−, are very similar and thus display similar crystal packing and a similar hydrogen-bonding network. Coplanarity of the aromatic ring and the protonated amidine fragment of the saturated ring is due to conjugation of the two π systems. Each I− anion is surrounded by three neighboring molecules, all lying approximately in a plane. Anions participate in only one N—HI− hydrogen bond, with HI distances of 2.7–3.0 Å, and their coordination spheres are completed by weak C—HI− contacts.