Abstract

Ultrafast spectroscopy on small molecules in solution offers a unique possibility for studying solvent-solute interaction, since the spectroscopic properties of the species involved often are well determined. In this context, photodissociation of tri-atomic molecules stands out as being particular interesting, since the dissociation of these species may follow several different solvent dependent reaction paths, while still being simple enough to allow for high level calculations of the reaction dynamics. Photodissociation and subsequent recombination have been studied in a number of tri-atomic molecules in solution including HgI₂, ${\text{I}}_3^{\text{-}},{\text{O}}_3^{\text{-}}$ and ${\text{ClO}}_2$.¹In these systems the photodissociation either leads to a vibrationally excited diatomic fragment which relaxes prior to the recombination, or a fast geminate recombination of the photo­fragments followed by vibrational relaxation. Apart from the important information about the primary quantum yields of these processes, ultrafast spectroscopy of these molecules have already reveled detailed information about solvent-solute interaction.

© 1998 IEEE