SYNTHESIS AND CRYSTAL-STRUCTURE OF (1,6-NH3C6H12NH3)(2)(1-NH3C10H7)(2)P6O18.2H(2)O

Synthesis and complete structural characterization by X-ray diffractio n, DTA, GTA and IR are given for a new cyclohexaphosphate: (1,6- NH3C6 H12NH3)(2) (1-NH3C10H7)(2)P6O18. 2H(2)O. This compound is monoclinic P 2(1)/c with the following unit-cell parameters: a = 11.861(2)Angstrom, b = 10.104(1)Angstrom, c = 19.664(6)Angstrom, beta = 96.44(2)degrees, and Z = 2. The crystal structure has been solved and refined to R = 0 .033 using 3928 independent reflections. The atomic arrangement can be described as layer organisation. Layers built by P6O18 ring anions an d water molecules spread in the plans (100). Between these layers are located the organic groups which form hydrogen bonds with oxygen atoms of P6O18 rings and water molecules. Geometrical characteristics of hy drogen bonds are described. The reported IR study is supported by a de laited theoretical group analysis applied to P6O18 with D-6h ideal loc al symmetry.