A 31P-SNP study of the photolysis of (2,4,6-trimethylbenzoyl) diphenylphosphine oxide in micelles of different sizes

31P stimulated nuclear polarization spectra and their dependence on time after photolysis of (2,4,6-trimethylbenzoyl)diphenylphosphine oxide in micellar solution of sodium octyl-(SOS) and dodecylsulfate (SDS) are investigated and discussed in terms of the numerical solution of teh stochastic Liouville equation for a microreactor model. The decay of the geminate radical pair is found to be about 2.5 times slower in SDS than in the SOS micelles due to a larger re-encounter rate in the latter one. Simulation of the experimental results further suggests J0 ∼ − 1.6 × 1010 rad/s for the exchange interaction at contact distance, and an increasing micellar size with increasing radical size.