Molecules (Basel, Switzerland)

https://eutils.ncbi.nlm.nih.gov/entrez/eutils/efetch.fcgi?db=pubmed&id=35566082&retmode=xml&tool=Litmetric&email=readroberts32@gmail.com&api_key=61f08fa0b96a73de8c900d749fcb997acc09 3556608220220716

1420-30492792022Apr23Molecules (Basel, Switzerland)MoleculesSkeletal Torsion Tunneling and Methyl Internal Rotation: The Coupled Large Amplitude Motions in Phenyl Acetate.273010.3390/molecules27092730The rotational spectrum of phenyl acetate, CH₃COOC₆H₅, is measured using a free jet absorption millimeter-wave spectrometer in the range from 60 to 78 GHz and two pulsed jet Fourier transform microwave spectrometers covering a total frequency range from 2 to 26.5 GHz. The features of two large amplitude motions, the methyl group internal rotation and the skeletal torsion of the CH₃COO group with respect to the phenyl ring C₆H₅ (tilted at about 70°), characterize the spectrum. The vibrational ground state is split into four widely spaced sublevels, labeled as A0, E0, A1, and E1, each of them with its set of rotational transitions and with additional interstate transitions. A global fit of the line frequencies of the four sublevels leads to the determination of 51 spectroscopic parameters, including the ΔE_A0/A1 and ΔE_E0/E1 vibrational splittings of ~36.4 and ~33.5 GHz, respectively. The V₃ barrier to methyl internal rotation (~136 cm^-1) and the skeletal torsion B₂ barrier to the orthogonality of the two planes (~68 cm^-1) are deduced.FerresLynnLInstitute of Physical Chemistry, RWTH Aachen University, Landoltweg 2, D-52074 Aachen, Germany.EvangelistiLucaL0000-0001-9119-1057Dipartimento di Chimica "G. Ciamician", Università di Bologna, Via Selmi 2, 40126 Bologna, Italy.MarisAssimoA0000-0003-2644-0023Dipartimento di Chimica "G. Ciamician", Università di Bologna, Via Selmi 2, 40126 Bologna, Italy.MelandriSoniaS0000-0002-0410-5833Dipartimento di Chimica "G. Ciamician", Università di Bologna, Via Selmi 2, 40126 Bologna, Italy.CaminatiWaltherWDipartimento di Chimica "G. Ciamician", Università di Bologna, Via Selmi 2, 40126 Bologna, Italy.StahlWolfgangWInstitute of Physical Chemistry, RWTH Aachen University, Landoltweg 2, D-52074 Aachen, Germany.NguyenHa Vinh LamHVL0000-0002-5493-8905Univ Paris Est Creteil and Université Paris Cité, CNRS, LISA, F-94010 Créteil, France.Institut Universitaire de France (IUF), F-75231 Paris, France.engJournal Article20220423

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