Spectroscopic investigations of nano-sized titanium(IV) complexes containing electron-rich oxygen-based ligands.

A convenient method has been explored to synthesize some nano-sized, mixed-ligand complexes of titanium(IV) with the general formula [Ti(acac)Cl(2-n)(L)(n)(OOCC(15)H(31))] (where Hacac=acetylacetone, HL=dibenzoylmethane or benzoylacetone and n=1 or 2). They have been synthesized by stepwise substitutions of chloride ions from titanium(IV) chloride with straight chain carboxylic acid and β-diketones. These were characterized by elemental analyses, molecular weight determinations, spectral (electronic, FTIR, (1)H NMR and powder XRD) and TEM studies. Conductance measurements indicated their non-conducting nature which may behave like insulators. Bidentate chelating nature of carboxylate and β-diketones anions in the complexes was established by their infrared spectra. LMCT bands were observed in the electronic spectra. Molecular weight determinations indicated mononuclear nature of the complexes. Powder XRD and transmission electron microscopy (TEM) studies indicated the particles of these were lying in the nano-size range. The complexes exhibited high resistance to hydrolysis. On the basis of these studies, coordination number 7 or 8 is assigned for titanium in the synthesized complexes.