(CN3H6)(2)center dot Zn4H5(PO4)(5), a new layered guanidinium zinc phosphate built up from 3-, 4-, and 8-ring units

The solution-mediated synthesis and single crystal structure of (CN3H6)(2) . Zn4H5(PO4)(5), a new guanidinium zinc phosphate, are described. The use of high-intensity synchrotron radiation was necessary to determine the correct unit cell for this phase, Unlike the previously described one-dimensional or three-dimensional guanidinium zinc phosphates, this material has a strongly layered nature. Vertex-linked ZnO4, HPO4, and H2PO4 building units self-assemble into complex sheets containing polyhedral 3-rings, 4-rings, and 8-rings. The intersheet guanidinium cations provide charge compensation and interact with the layers via N-H ... O hydrogen bonds, Crystal data: (CN3H6)(2) . Zn4H5 (PO4)(5), M-r = 861.57, monoclinic, space group I2/a (No, 15), a = 23.770 (2) Angstrom, b = 5.1036 (5) Angstrom, c = 18.100 (2) Angstrom, beta = 94.491 (2)degrees, V = 2189.0 (5) Angstrom(3), Z = 4, R(F) = 0.047, R-w(F-2) = 0.121 (2322 reflections, 168 parameters). (C) 1999 Academic Press.