Alternative calculations for internal rotations: Assessment via Mathieu and multi-Fourier term potentials Original Research Article

We demonstrate the accuracy of our recently proposed calculational methodology for molecular torsional energy modes by comparing the levels of a 3-fold symmetric potential with the corresponding known eigenvalues of the analytic Mathieu equation. We further compare our calculation with those of other authors previously carried out for trifluoroacetyl bromide and propene using a 2-term Fourier potential.