SYNTHESIS AND CHARACTERIZATION OF 2 NOVEL FIBROUS TITANIUM PHOSPHATESTI2O(PO4)(2)CENTER-DOT-2H(2)O

New crystalline phases of fibrous titanium(IV) oxophosphates were prep ared hydrothermally from titanium(IV) chloride in phosphoric acid solu tions. The influence of several factors (concentration of reagents, mo lar ratio P:Ti in the reaction mixture, and reaction times) was studie d. A phase diagram of the system is given. On the basis of elemental a nd thermal analysis, X-ray powder diffraction, P-31 MAS NMR, and IR sp ectroscopy, the formula Ti2O-(PO4)(2) . 2H(2)O was assigned to the nov el compounds. The new phases (pi-TiP and rho-TiP) have different struc tures. The crystal structure of rho-TiP was solved from X-ray powder d ata and was shown to be of the framework type with tunnels parallel to the c-axis direction. The absence of n-alkylamine intercalation proce sses for both compounds and other physical and behavioral similarities suggests a framework type structure for pi-TiP also. The ion-exchange behavior toward alkali and alkaline earth ions was studied.