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Updated: Sep 26, 2025
06:08
Time-resolved Photophysical Characterization of Triplet-harvesting Organic Compounds at an Oxygen-free Environment Using an iCCD Camera
Published on: December 27, 2018
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Radiative relaxation in isolated large carbon clusters: Vibrational emission versus recurrent fluorescence
O Lacinbala1, F Calvo2, C Dubosq3
1Université Paris-Saclay, CNRS, Institut des Sciences Moléculaires d'Orsay (ISMO), 91405 Orsay, France.
The Journal of Chemical Physics
|April 16, 2022
Summary
Recurrent fluorescence (RF) in carbon clusters is competitive with vibrational emission. This finding impacts understanding interstellar medium photophysics and the origin of cosmic infrared emission bands.
Area of Science:
- Physical Chemistry
- Astrochemistry
- Computational Physics
Background:
- Carbon clusters are relevant to interstellar dust and molecular clouds.
- Understanding their photophysical properties is key to interpreting astronomical observations.
Purpose of the Study:
- To theoretically investigate recurrent fluorescence (RF) in isolated carbon clusters.
- To analyze the influence of internal energy, cluster size, and structure on RF.
- To determine vibrational relaxation kinetics and IR emission spectra.
Main Methods:
- Monte Carlo simulations were employed.
- Vibrational density of states were computed using the harmonic approximation.
- RF competitiveness with vibrational emission was assessed.
Main Results:
- Recurrent fluorescence (RF) was found to be highly competitive with vibrational emission.
- IR emission spectra are significantly influenced by RF.
- An energy gap law governs the RF rate constant's dependence on the electronic excitation state.
Conclusions:
- The study provides insights into the photophysics of carbon clusters.
- Results contribute to understanding the carriers of extended red emission and sub-aromatic infrared bands in the interstellar medium.
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