On mechanism of population of the I2(β) state under photolysis of the I2 + SF6 mixture

Pressure dependences of luminescence intensities of the I 2 ( E 0 g + → B 0 u + , D 0 g + → X 0 g + and β 0 g + → A 1 u ) transitions, temporal histories of the luminescence and luminescence excitation spectra at different time delays from the beginning of the probe laser pulse under OODR photolysis of the I2 + SF6 mixture have been measured. A comparison of experimental dependences with those obtained after detailed analysis of kinetics of spontaneous and collision-induced processes in a free iodine molecule has been made. We have established that there is additional optical channel of population of the I2(β) state, namely, direct optical pumping of the SF6I2(IP) complexes, accompanied by their predissociation to the SF6 + I2(β) products.