title: The optical activity of carvone: a theoretical and experimental investigation.
abstract: The optical rotatory dispersion (ORD) and circular dichroism of the conformationally flexible carvone molecule has been investigated in 17 solvents and compared with results from calculations for the "free" (gas phase) molecule. The G3 method was used to determine the relative energies of the six conformers. The optical rotation of (R)-(-)-carvone at 589 nm was calculated using coupled cluster and density functional methods, including temperature-dependent vibrational corrections. Vibrational corrections are significant and are primarily associated with normal modes involving the stereogenic carbon atom and the carbonyl group, whose n → π∗ excitation plays a significant role in the chiroptical response of carvone. Without the inclusion of vibrational corrections the optical rotation calculated with CCSD and DFT has the opposite sign of experimental data. Calculations of optical rotation performed in solution using the polarizable continuum model were also opposite in sign when compared to that of the experiment.
authors.affiliation: Department of Physics and Department of Chemistry, University of Tennessee, Knoxville, Tennessee 37996, USA. jlamber9@utk.edu
authors.forename: Jason
authors.initials: J
authors.lastname: Lambert
authors.forename: R N
authors.initials: RN
authors.lastname: Compton
authors.forename: T Daniel
authors.initials: TD
authors.lastname: Crawford
mesh_terms: D000081005:Cyclohexane Monoterpenes; D039821:Monoterpenes / Q000737:chemistry*; D011789:Quantum Theory; D013696:Temperature; D014732:Vibration
chemical_list: D000081005:Cyclohexane Monoterpenes; D039821:Monoterpenes; C006923:carvone