Ab initio prediction of vibrational absorption and circular dichroism spectra of chiral natural products using density functional theory: Camphor and Fenchone

Density functional theory (DFT) is used to assign the vibrational unpolarized absorption and circular dichroism spectra of two monoterpenes: camphor and fenchone. Calculations are carried out using the hybrid functionals B3PW91 and B3LYP at the TZ2P and 6-31G* basis set levels using direct analytical derivative methods and (for the calculation of atomic axial tensors) GIAOs. B3PW91/TZ2P calculations are in best agreement with experiment and provide the most convincing assignment of the spectra.