Ultrafast dynamics of chlorine dioxide in solution upon excitation of the A/spl tilde//sup 2/A/sub 2//spl larr/X/spl tilde//sup 2/B/sub 1/ transition

Summary form only given. Much effort has been put in the elucidation of the photochemistry of ClO/sub 2/ in the gas and the condensed phases since the outcome of the reaction pathways may have strong implications for sun-light induced stratospheric chemistry. Gas phase experiments and ab initio calculations have shown the complexity of the photochemical dynamics of ClO/sub 2/, that can dissociate along the pathways ClO+O or Cl+O/sub 2/. It is now clear that the excited state dynamics of the A/spl tilde//sup 2/A/sub 2/ state is determined by a multitude of conical intersections to the optically weak 1/sup 2/A/sub 1/ and the dark 1/sup 1/B/sub 2/ states. In the gas phase the lifetimes of these states before dissociation to the photoproduct can be determined with femtosecond time-resolved mass and photoelectron spectroscopy. We have performed pump-probe spectroscopy with 50 fs temporal resolution, where pump and probe were centered at 403 nm, produced by a frequency-doubled l-kHz amplified Ti:sapphire system, in order to get more insight in the initial dynamics in solution, where features like cage effect, recombination and relaxation to the ground state as well as reaction with the solvent may occur.