Low-temperature absorption and fluorescence spectra of phthalocyanine in n-alcanes and in polyethylene (Shpolskii's effect)

Absorption and fluorescence spectra of free base phthalocyanine were studied in matrices of n-alcanes (C₈H₁₈, C₁₂H₂₆, C₁₆H₃₄) and polyethylene at 77 K and 4·2 K. The spectra show quasi-line structure whose multiplicity increases with increasing number of carbon atoms of the solvent and decreasing temperature. In the low-temperature spectra of phthalocyanine in polyethylene films only band spectra have been observed.I wish to thank Prof. DrSc K.Vacek, Head of The Department of Chemical Physics, Charles University for stimulating discussions.