Low Temperature Physics: 38, 727 (2012); https://doi.org/10.1063/1.4746794 (5 pages)
Физика Низких Температур: Том 38, Выпуск 8 (Август 2012), c. 917-923 ( к оглавлению , назад )
Electronic spectroscopy, stimulated emission and persistent spectral hole-burning of cryogenic nitrogen matrices doped with tetrabenzoporphin
S.M. Arabei1, J.-P. Galaup2*, J.G. McCaffrey3, N. Shafizadeh4, and C. Crépin4
1Belarusian State Agrarian and Technical University, Minsk, Belarus
2Laboratoire Aimé Cotton, CNRS & Université Paris-Sud 11, Orsay, France
3Department of Chemistry, National University of Ireland, Maynooth, Ireland
4Institut des Sciences Moléculaires d'Orsay, CNRS & Université Paris-Sud 11, Orsay, France
Received April 20, 2012
This paper deal with our on-going work on the electronic spectroscopy of tetrapyrrole molecules embedded in cryogenic hosts. Under nanosecond laser excitation of the free-base tetrabenzoporphin molecules in a nitrogen matrix at 8 K, increasing the laser pulse energy results in essential enhancement of the intensity of one or several vibronic emission lines to take place in the fine-structure fluorescence spectrum. The observed intense monochromatic radiation possesses characteristics of stimulated radiation being realized as a result of a transition from the purely electronic S1 level to a vibrational sublevel of the S0 state, corresponding to excitation of stretching C–C vibrations of the tetrapyrrole methane bridges. We also report on persistent spectral hole-burning effects. The analysis of the holes and antiholes formation gives some insight on the photochemical properties of tetrabenzoporphin in a nitrogen matrix.
PACS: 33.50.–j Fluorescence and phosphorescence; radiationless transitions, quenching (intersystem crossing, internal conversion);
Ключевые слова: fluorescence, stimulated emission, cryogenic matrices, tetrabenzoporphin, spectral hole-burning.