Relaxation of atomic iodine

Finally, we discuss briefly the results of Donovan and Husain126 on the relaxation of I(52Pi- i), for which AE = 7603 cm-1. The problem is even more complex than the foregoing, because the splitting is large and the extent of vibrational excitation accompanying electronic deactivation is not known. Atomic iodine in the 5 2Pi state can be produced by flash photolysis of various iodides, 

CF3I being particularly suitable because the residual parent compound is only moderately effective at inducing relaxation. Decay rates are conveniently measured by photometry of the atomic lines in the far ultraviolet. Some rate coefficients are listed in Table 13. The inert gases are not effective for this process because the splitting is too large to permit pure E-T relaxation to occur at a measurable rate. 

Deactivation by I2 is very fast and corresponds to Z 15 the efficiency of relaxation may be comparable with the rate of the chemical exchange 

It has recently been demonstrated127 that 1(5 2Pi) reacts with propane I(52P ) + C3H8 - HI+C3H7 

Clearly a great deal of experimental and theoretical work is required to clarify some of the points which have been raised in this section. 

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