title: Electronic Spectroscopy of Methylcyanodiacetylene (CH3C5N).
abstract: The results of a study devoted to the electronic spectroscopy of gaseous, solid, and cryogenic matrix-isolated methylcyanodiacetylene (CH3C5N) are reported. UV absorption and optical phosphorescence spectra of the compound are described here for the first time, and the corresponding vibronic assignments are proposed. UV absorption, studied directly or through the excitation of phosphorescence, revealed the B˜1E--X˜1A1system, very weak A˜1A2-X˜1A1bands, and a strong, broad absorption feature, tentatively identified as D˜1E-X˜1A1. Spectral measurements were assisted by quantum chemical calculations at the DFT and ab initio (coupled cluster) levels of theory.
authors.affiliation: Institute of Physical Chemistry, Polish Academy of Sciences, Kasprzaka 44, 01-224, Warsaw, Poland.
authors.forename: Michał
authors.identifier: http://orcid.org/0000-0002-8592-5912
authors.initials: M
authors.lastname: Turowski
authors.affiliation: Institute of Physical Chemistry, Polish Academy of Sciences, Kasprzaka 44, 01-224, Warsaw, Poland.|Institut des Sciences Moléculaires d'Orsay (ISMO), CNRS, Univ. Paris-Sud, Université Paris-Saclay, F-91405, Orsay, France.
authors.forename: Urszula
authors.initials: U
authors.lastname: Szczepaniak
authors.affiliation: Institute of Physical Chemistry, Polish Academy of Sciences, Kasprzaka 44, 01-224, Warsaw, Poland.
authors.forename: Thomas
authors.identifier: http://orcid.org/0000-0003-2336-4248
authors.initials: T
authors.lastname: Custer
authors.affiliation: Institute of Physical Chemistry, Polish Academy of Sciences, Kasprzaka 44, 01-224, Warsaw, Poland.
authors.forename: Marcin
authors.initials: M
authors.lastname: Gronowski
authors.affiliation: Institute of Physical Chemistry, Polish Academy of Sciences, Kasprzaka 44, 01-224, Warsaw, Poland.
authors.forename: Robert
authors.initials: R
authors.lastname: Kołos
keywords: astrochemistry; cyanoacetylenes; electronic spectroscopy; gas and solid phases; matrix isolation