Time-resolved spectroscopy of "hot" luminescence as a method for investigation of picosecond relaxation in molecular systems

The example of perylene molecules in a frozen paraffin matrix was used in the first-ever observation of the time dependence of the intensity of vibronic lines in a luminescence spectrum, which was a direct manifestation of intramolecular relaxation in the S₁ state. Spreading of a picosecond signal in a highresolution monochromator was prevented in a new system with subtraction of dispersion, which ensured that the best attainable parameters (from the point of view of the indeterminacy principle) were achieved in timeresolved spectroscopy.