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.