STRUCTURAL INVESTIGATIONS ON TICL4 SOLUTIONS

Aqueous titanium tetrachloride solutions of different concentrations w ere examined by large-angle X-ray scattering (LAXS), X-ray absorption spectroscopy (XAS) and Raman scattering. Analysis of X-ray absorption near edge structure (XANES) proved a predominant octahedral symmetry a round titanium. Raman scattering revealed the linkage of titanium-oxyg en octahedra, but only in higher concentrated solutions the incorporat ion of chloride ions into the first coordination sphere of titanium wa s provable. The LAXS experiments enabled the derivation of a structura l model for the linked titanium species consisting of corner-sharing t itanium-oxygen octahedra forming dimers and trimers. Commercially used TiCl4 solutions (188 to 641 g TiCl4/l) are therefore already prehydro lyzed and do not contain significant amounts of unhydrolyzed Ti-Cl-bon ds.