Kinetics of OH Radicals from Flame Emission Spectra. II. Rotational and Vibrational Distribution Functions and Temperature Determinations in the 2Σ+—2Π Transition of OH

Abstract

Rotational and vibrational distribution functions for a rotating oscillator are developed for a steady state with non-equipartition of energy such as might be found for electronically excited species in a flame. Methods are described for the separate spectrocsopic determination of rotational and vibrational equilibria and ``temperatures'' for the case of thermal equilibrium and for the case of a non-equipartition distribution of energy. These methods are applied to the study of electronically excited OH radicals in an equimolar oxynatural gas (88 percent CH4) flame. Rotation-vibration equilibrium with a rotation-vibration temperature of ∼2550°K was found. Analysis of the data indicates that the vibrational transition probabilities for the 2Σ+—2Π transition calculated in Part I of this paper are accurate to about the 10 percent claimed in that communication.