Differential cross section as a function of the product internal state : the F+I2→IF(ν,J)+I reactive collision

We have measured the differential cross section of the F+I2→IF+I reactive collision as a function of the rovibrational state of IF. This measurement was made by an analysis of the Doppler profiles of the laser-induced fluorescence detection signals, as suggested by Kinsey [J. Chem. Phys. 66, 2560 (1977)]. This paper describes in detail the experiment and the way we analyze the data to deduce the differential cross section. The shape of the cross section appears to vary noticeably with the rotational energy of IF and to a lesser extent with its vibrational energy. Several partial explanations are possible, and the choice remains not clear as long as we have no precise information on the potential-energy surfaces of the I2F system.