Vandenbussche et al. [72] presented a statistical validation of
absolute configuration assignment using VCD for a series of quinolizine
molecules. Polavarapu and Covington [73] presented
dissymmetry factors as similarity measures for the analysis of VCD,
ECD, and Raman optical activity spectra. The scientific community
has not reached consensus in using a protocol to obtain a similarity
factor when comparing experimental and calculated chiroptical
spectra. Most often the harmonic approximation is used for the
calculations so that anharmonic contributions are neglected which
will be one of the reasons of mismatch between experiment and
calculation. The importance of anharmonicity was shown by Cappelli
et al. [74] for the test molecule formaldehyde. Current computer
resources often limit a full anharmonic treatment of
molecules larger than 30 atoms.