ENERGY TRANSFER PROCESSES IN THE XENON SENSITIZED PHOTOLYSIS OF SOCl2, S2Cl2 and PCl3

K. Wojciechowski, M. Rosa, M. Symanowicz, A. Jowko, M. Foryś

Department of Chemistry, Agricultural and Pedagogical University, 08-110 Siedlce, 3 Maja 54, Poland


The kinetics and mechanism of energy transfer from Xe (3P1,3P2) atoms to RCl (RCl = SOCl2, S2Cl2 and PCl3) molecules have been investigated by measuring XeCl (B,C) ® XeCl (X,A) fluorescence intensity at stationary conditions. Steady-state analysis of the dependence of the fluorescence intensity on xenon and additive pressure shows that energy transfer from xenon excited atoms to chlorine donor molecules occurs in the two- and three-body reactions:
Xe (3P1, 3P2) + RCl ® Products
Xe (3P1, 3P2) + RCl + Xe ® Products
It has been shown that the third order reaction is a very effective channel of the decay of xenon excited atoms at xenon pressures above 20-50 Torr. The rate constants for this reactions were found to be (1.6 ± 0.2)·10-28 and (1.85 ± 0.3)·10-28 and (2.7 ± 0.3)·10-28 cm6s-1 for RCl = SOCl2, S2Cl2 and PCl3, respectively. XeCI* excimers are formed in these reactions with efficiency of 0.42, 0.39 and 0.49 for SOCl2, S2Cl2 and PCl3, respectively.