Collisional quenching of CCl2 radicals in the A(1)B(1) (0,4,0) and a(3)B(1) states by alcohols

The experimental quenching data for CCl2 in the excited state, A(1)B(1) (0, 4,0), by alcohols were obtained through observing its time-resolved total f luorescence signal, which showed a superposition of two exponential decay c omponents. The quenching rate constants K-A for CCl2 (A) State and K-a for CCl2 (a) state were derived by analyzing the experimental data according to a proposed three-level-model to deal with CCl2 (X(1)A(1),A(1)B(1),a(3)B(1) ) system. K-A and K-a increase on the whole with increasing the number of C -H bonds in alcohol molecules. (C) 2001 Elsevier Science B.V. All rights re served.