An electron spin resonance study of the hydrolytic products formed by titanium(III) trichloride in aqueous and mixed aqueous solutions and frozensolutions

X-band e.s.r. measurements of aqueous solutions containing titanium(III) trichloride at room temperature and 77 K provide evidence for the formation of aquated Ti(OH)2+ as the major product of hydrolysis at low pH, along with dimeric species Ti2(OH)24+ formed in small amounts. When certain organic solvents miscible with water are present a further hydrolytic product suggested to be Ti2(OH)5+ is found at low pH. Consideration of an interaction spin Hamiltonian which takes into account the symmetry properties of the paramagnetic ion pair systems makes possible the computer simulation of the experimental spectra due to the dimeric species. By this procedure the magnetic parameters associated with the titanium(III) dimers have been evaluated along with a determination of the titanium(III)-titanium(III) ion separations. This information has been used to suggest possible structures for the dimeric species.