IDENTIFICATION OF B AND C-TYPE CORIOLIS INTERACTIONS IN ${\tilde {A}^{1}A_{u}}$ ACETYLENE-$D_{2}$ USING DOUBLE RESONANCE SPECTROSCOPY

Abstract

The identification of B and C-type Coriolis interactions in the $\tilde{A} ^{1}{{A}{u}}$ state is greatly facilitated by recording double resonance spectra to the vibrationless level of the previously assigned $\tilde {C} ^{1}A{g}$ electronic $state^{1}$ of $C_{2}D_{2}$. Analysis of the J and K rotational structure manifest in the double resonance spectra of the $\tilde{C}$ state allows the identification of B and C-type Coriolis perturbations in the $\tilde{A}$ state. This analysis can provide direct evidence of the location of the dark $A_{g}$ and $B_{g}$ symmetry vibrational states involving $\nu_{4}, \nu_{5}$ and $\nu_{6}$ excitation in the still not fully characterized $\bar {A} ^{1}A_{u}$ state of acetylene.