Infrared Band Contours. II. The Influence of Coriolis Coupling on Oblate Symmetric-Top Bands

Abstract

The influence of first-order Coriolis coupling on the shapes of perpendicular infrared bands of oblate symmetric-top molecules has been treated generally and quantitatively. The results are expressed in a table of band envelopes for various ratios of the moments of inertia and various values of the coupling parameter, ζ. A pronounced dependence of the band envelope on the extent of coupling has been found which makes it possible to evaluate the Coriolis constant ζ with good accuracy by comparing experimental and computed band envelopes. The scale factor required to equate the computed band envelope with the observed one provides a measure of the vibrational transition moment. In many cases this will provide the easiest, and perhaps the most accurate, method of obtaining this quantity.