Silver Cyanoguanidine Nitrate Hydrate: Ag(C2N4H4)NO3·½ H2O, a Cyanoguanidine Compound Coordinating by an Inner Nitrogen Atom

Silver(I) cyanoguanidine nitrate hydrate, Ag(C2N4H4)NO3·½H2O, was synthesized as the first cyanoguanidine solid-state complex in which monovalent Ag is coordinated through inner nitrogen N atoms. Its structure was characterized by single-crystal X-ray diffraction, crystallizing in the acentric orthorhombic space group P21212 with a = 10.670(3) A, b = 18.236(5) A, and c = 3.5078(9) A. The differing chemical bondings of Ag(C2N4H4)NO3·½H2O and Ag(C2N4H4)3NO3 were compared on the basis of first-principle calculations.