Investigation of transient state and dynamics of photochemical transformations of chromone molecules

Results of investigation of the phototransformation dynamics of chromone molecules by means of a transient-state spectroscopy are presented. Changes in the spectrum of the optical density of chromone compounds dissolved in toluene in the process of their phototransformation are obtained on a time scale ranging from several hundred femtoseconds to several hundred picoseconds. Relaxation of an induced absorption spectrum is described by a biexponential function with characteristic time constants on the order of several picoseconds and several nanoseconds. A scheme of the phototransformation dynamics of chromone molecules corresponding to the observed dynamics of absorption spectra is proposed.