Crossed-beam studies of some chemiluminescent reactions producing IF

Abstract

This paper describes the study of the chemiluminescent branch of the reactive collisions of molecular fluorine F₂ with a series of iodides, HI, CF₃I, CH₃I, CH₂I₂ and CHI₃. All these reactions can produce IF in its A and B excited states, but in crossed molecular beam conditions, only the B state can contribute to the observed chemiluminescence signals. These signals have been studied as a function of the reactant densities and of the collision kinetic energy, providing in particular estimates of the reaction thresholds. The spectrum of the F₂+HI chemiluminescence has been recorded and analyzed in terms of the IF B state rovibrational distribution. To explain our observations, we have extended a model, previously developed by C. C. Kahler and Y. T. Lee for the I₂+F₂ chemiluminescent reaction, by introducing a migratory step.