title: Keto-enol tautomerism and conformational landscape of 1,3-cyclohexanedione from its free jet millimeter-wave absorption spectrum.
abstract: The free jet millimeter-wave absorption spectrum of 1,3-cyclohexanedione has been investigated in the 59.6-74.4 GHz frequency range, and the rotational spectra of two conformational species, the chair-diketo and boat-diketo, and probably one excited vibrational state belonging to the chair-diketo form have been assigned. Quantum chemical calculations, performed at the B3LYP/6-311++G** and MP2/6-311++G** levels, were used to characterize the potential energy surface minima. The potential energy surface related to the interconversion of the observed diketonic species was modeled at the DFT level.
authors.affiliation: Dipartimento di Chimica "G. Ciamician", Università di Bologna , Via Selmi 2, I-40126 Bologna, Italy.
authors.forename: Camilla
authors.initials: C
authors.lastname: Calabrese
authors.forename: Assimo
authors.initials: A
authors.lastname: Maris
authors.forename: Luca
authors.initials: L
authors.lastname: Evangelisti
authors.forename: Laura B
authors.initials: LB
authors.lastname: Favero
authors.forename: Sonia
authors.initials: S
authors.lastname: Melandri
authors.forename: Walther
authors.initials: W
authors.lastname: Caminati