A PRINCIPAL COMPONENT ANALYSIS OF THE METHYL-FLUORIDE POLAR TENSORS

The principal component method is applied to the analysis of the alter native polar tensor data set values for CH3F and CD3F. Moller-Plesset perturbation and configuration interaction ab initio wavefunction resu lts are necessary for a secure selection of the correct polar tensor v alues from the sets of values satisfying the isotopic invariance crite rion for the A1 symmetry derivatives. The preferred polar tensor value s corresponding to the E symmetry species can only be determined using Coriolis interaction information, the isotopic invariance criterion a nd molecular orbital results at the Moller-Plesset perturbation or con figuration interaction levels. The results reported in this paper are in agreement with those obtained previously using the isotopic invaria nce criterion, Coriolis interaction information and the results of CND O/2 molecular orbital calculations.