The Photo-Ionization of Molecules in Solutions. IV. Electron Capture and Charge Transfer Fluorescence Phenomena Occurring between N, N, N′, N′-Tetramethyl-p-phenylenediamine and Electron Acceptors in Organic Solvents

A mixture of N, N, N′, N′,-tetramethyl-p-phenylenediamine (TMPD) and pyrene in some rigid matrices was illuminated at a low temperature in the near ultraviolet region. It was found that TMPD+, pyrene anion, and solvated electrons are formed in the medium. The ratio of the formation of pyrene anion and TMPD+ has been studied at various concentrations of pyrene. The behavior of the photo-ejected electron, particularly its extent of migration has then been discussed on the basis of the experimental results. The thermoluminescence spectrum of the UV-irradiated matrix containing TMPD and pyrene was measured after it had been illuminated in the infrared region. The luminescence may tentatively be assigned to the charge transfer fluorescence. The emission spectra were investigated for a mixture containing TMPD and α-methylnaphthalene in several solvents by exciting the TMPD. It was found that a new emission band appeared at 480 mμ. It was assigned to the charge transfer fluorescence.