CORIOLIS COUPLING IN AR-HCL

The PI-bending state of Ar-HCl has been examined by tunable far-infrared spectroscopy and the J dependence of the Coriolis coupling to the SIGMA-bending and SIGMA-stretching vibrations analyzed. The Coriolis coupling constants obtained are only slightly smaller than those previously observed in the complex containing a quantum of HCl of vibrational excitation (3.2% for the PI-SIGMA-bend coupling and 4.5% for the PI-SIGMA-stretch coupling). Deperturbed rotational constants determined for the SIGMA-bending state of the Cl-35 and Cl-37 species cannot be used in conjunction with simple moment of inertia expressions to support the predicted antihydrogen bonded geometry for that state. Comparisons between the ground states and the PI-states of the series Ar-HX (X = F, Cl, Br) are discussed.