Sensitivity of photoelectron circular dichroism to structure and electron dynamics in the photoionization of carvone and related chiral monocyclic terpenone enantiomers

The photoelectron circular dichroism that arises in the angular distribution of photoelectrons emitted from the carbonyl group in randomly oriented pure enantiomers of carvone, and a number of carvone derivatives, is investigated by continuum multiple scattering calculations. Core ionization of carbonyl C 1s orbitals is examined for six different isopropenyl tail conformations of carvone. These show clear differences of behavior both between axial and equatorial conformations, and between the three rotational conformers of each. The pronounced dependence of the dichroism on orientation of a tail grouping, itself remote from the localized initial C 1s site, indicates the presence of long range final state photoelectron scattering effects. Analogous data for the outermost valence orbital, partially localized on the carbonyl group, are also presented. The apparently enhanced sensitivity of the dichroism exhibited in this work is discussed in terms of the particular dependence on photoelectron interference effects that is probed by the dichroism measurement and is contrasted with the usual beta parameter and cross section determinations. (c) 2006 American Institute of Physics.