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Published on: July 17, 2018
Cryogenic Photochemical Synthesis and Electronic Spectroscopy of Cyanotetracetylene
Urszula Szczepaniak1,2, Robert Kołos2, Marcin Gronowski2
1Institut des Sciences Moléculaires d'Orsay, UMR8214, CNRS Univ. Paris-Sud, Université Paris-Saclay , F-91405 Orsay, France.
Abstract:
HC9N is a molecule of astrochemical interest. In this study, it was produced in cryogenic Ar and Kr matrices from UV-photolyzed diacetylene/cyanodiacetylene mixtures. Its strong phosphorescence was discovered and served for the identification of the compound. Vibrationally resolved phosphorescence excitation spectra gave insight into excited singlet electronic states. Two electronic systems were observed around 26 000-34 000 cm-1 and 35 000-50 000 cm-1. Energies of the second excited singlet and the lowest triplet state were derived from analysis of these systems. Vibrational and electronic spectroscopic features were assigned with the assistance of density functional theory calculations. Some trends concerning the electronic spectroscopy of HC2n+1N family molecules are presented.
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