title: Accurate spectroscopy of polycyclic aromatic compounds: from the rotational spectrum of fluoren-9-one in the millimeter wave region to its infrared spectrum.
abstract: The rotational spectrum of fluoren-9-one, a small oxygenated polycyclic aromatic hydrocarbon, has been recorded and assigned in the 52-74.4 GHz region. The determined small negative value of the inertia defect (-0.3 u Å(2)) has been explained in terms of vibrational-rotational coupling constants calculated at the B3LYP/cc-pVTZ level of theory. Vibrational anharmonic analysis together with second-order vibrational perturbation theory approximation was applied both to fluorenone and its reduced form, fluorene, to predict the mid- and near-infrared spectra. The data presented here give precise indication on the fluorenone ground state structure, allow for an accurate spectral characterization in the millimeter wave and infrared regions, and hopefully will facilitate extensive radio astronomical searches with large radio telescopes.
authors.affiliation: Dipartimento di Chimica "Giacomo Ciamician", Università degli Studi di Bologna, via Selmi, 2, I-40126 Bologna, Italy.
authors.forename: Assimo
authors.initials: A
authors.lastname: Maris
authors.affiliation: Dipartimento di Chimica "Giacomo Ciamician", Università degli Studi di Bologna, via Selmi, 2, I-40126 Bologna, Italy.
authors.forename: Camilla
authors.initials: C
authors.lastname: Calabrese
authors.affiliation: Dipartimento di Chimica "Giacomo Ciamician", Università degli Studi di Bologna, via Selmi, 2, I-40126 Bologna, Italy.
authors.forename: Sonia
authors.initials: S
authors.lastname: Melandri
authors.affiliation: Departamento de Química-Física y Química Inorgánica, Facultad de Ciencias, Universidad de Valladolid, Paseo Belén 7, E-47005 Valladolid, Spain.
authors.forename: Susana
authors.initials: S
authors.lastname: Blanco