External Magnetic Field Effects on Shape Anisotropy of TiO₂ Nanostructures Grown from a Paramagnetic Ti(III) Precursor

A new Ti(III) precursor [TiCl 2 (O i Pr)(pyridine) 3 ] ( 1 ) was employed in magnetic field-assisted chemical vapor deposition (CVD) to induce external field effects on the paramagnetic metal (d 1 ) center during film growth. Gas-phase decomposition of 1 under variable magnetic fields (0–0.50 T) showed pronounced shape anisotropy in as-grown TiO 2 films confirmed by distinct morphological patterns and preferred crystallographic orientation of the grains. The electronic structure of the Ti–O manifold derived from X-ray absorption spectroscopy showed the formation of well-defined anatase-type TiO 6 subunits in the case of field-assisted processes (0.50 T), whereas distortions toward TiO 6 units of the rutile modification were seen for the zero-field experiments. The contactless control of the morphology and micro- and electronic structure of the CVD deposits through the field influence offers new opportunities for in situ control of material characteristics.