STUDY OF THE V3 AND 2V4 INTERACTING STATES OF 12CF4

The interacting v 3 and 2v 4 states of 12CF4 have been analysed by the tensorial formalism developed by the spectroscopic group at the Universite de Bourgogne. Experimental data included are the v 3 and 2v 4 infrared absorption bands measured by diode lasers, and pure rotational radiofrequency and microwave transitions in the v 3 state. The v 4 band spectrum taken by Fourier transform spectrometer is also included to constrain the 2v 4 band constants. The observed badly perturbed v 3 R-branch spectrum and pure rotational transitions measured with an accuracy of 100 kHz are reproduced successfully with accuracies of 150 kHz and 450 kHz, respectively. Relations with the Hecht (Robiette) notation are discussed.

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