Pseudopyramidal building units in mixed inorganic/organic network solids: Syntheses, structures, and properties of alpha- and beta-ZnHPO3 center dot N4C2H4

The syntheses, crystal structures, and some properties of alpha- and beta - ZnHPO3.N4C2H4 are reported. These polymorphic phases are the first organica lly templated hydrogen phosphites. They are built up from vertex-sharing HP O3 pseudopyramids and ZnO3N tetrahedra, where the Zn-N bond represents a di rect link between zinc and the neutral 2-cyanoguanidine template. alpha -Zn HPO3.N4C2H4 is built up from infinite layers of vertex-sharing ZnO3N and HP O3 groups forming 4-rings and 8-rings. beta -ZnHPO3.N4C2H4 has strong one-d imensional character, with the polyhedral building units forming 4-ring lad ders. Similarities and differences to related zinc phosphates are discussed . Crystal data: alpha -ZnHPO3.N4C2H4, monoclinic, P2(1)/c, a = 9.7718 (5) A ngstrom, b = 8.2503 (4) Angstrom, c = 9.2491 (5) A, beta = 104.146 (1)degre es, Z = 4. beta -ZnHPO3.N4C2H4, monoclinic, C2/c, a = 14.5092 (9) Angstrom, b = 10.5464(6) Angstrom, 10.3342 (6) Angstrom, beta = 114.290 (1)degrees, Z = 8.