Ozone Ultraviolet Photolysis. IV. O2† + O(3P) Vibrational Energy Transfer

The rate of relaxation of vibrationally excited ${\mathrm{O}}_2^{†}$ in high vibrational levels of the ${\mathrm{X\; \hspace{0.17em}}}^3{\Sigma }_g^{-}$ ground state was measured following flash photolysis of O₃−Ar mixtures. The relaxation rate is proportional to the O(³P) concentration when the [O(³P)]/[O₃] ratio is not small. The data are analyzed assuming that the constants conform to the systematic relationship, $k_{\mathrm{ij}}{\mathrm{=\; k}}_{10}\text{[1+β(i−1)]\hspace{0.17em}}\exp \text{[−γ(i−j−1)]}$ , where i is the initial state and j is the final state with i>j. β determines the dependence on energy level and γ the dependence on multiple quantum transitions. Using $k_{10}{\text{= 6 × 10}}^8$ liter/mole·sec from Kiefer and Lutz, the values $\text{β=0.04}$ and $\text{γ=0}$ best represent the data. That is, the large increase in relaxation rate with energy level is best explained by multiple quantum transitions. With this interpretation the shock‐tube studies of Kiefer and Lutz, the trajectory calculations by Brieg, and the results of this study are self‐consistent.