PROTON-EXCHANGE EFFECTS IN LASER PHOTOLYSTIC P-BENZOSEMIQUINONE SPIN-POLARIZED RADICALS

The TRESR spectra of benzosemiquinone radical and the ethylene glycol ketyl radical formed from laser photolysis of P-benzoquinone in ethyle ne glycol or ethylene glycol/water systems are presented. The photon e xchange between p-benzosemiquinone radicals PBQH(.) and their protonat ed forms PRQH(+) is studied by adding H2SO4 to the solution. The exper imental results show that different hyperfine lines for PBQH(+) have d ifferent time-dependence which depend upon tile fraction of the overal l number of nuclear spin states, and that the lines with smaller fract ion are decay fast.