The influence of vibration-rotation interaction on intensities in the electronic spectra of diatomic molecules I. The hydroxyl radical

Abstract

The effect of vibration-rotation interaction on transition probability is examined in detail for the 2 E + - 2 lI i transition of the hydroxyl radical, using a Morse-Pekeris model. It is shown to have a significant effect on the rotational temperature (of the order of 200° at 3000 °K) for the (0, 0) b and and to be especially important for the (0, 1) band. The variation of transition moment with internuclear distance is examined and an expression of the form R e ( r ) = constant x e -2.5r where r is the internuclear distance in angstroms is recommended. With this value, corrections are obtained to rotational temperatures and the f value for the Q 1 (6) line of th e (0, 0) band is altered to 1.0 ±0.5 x 10 -3 . Calculations for the OD radical are also presented.