The Measurements of Quenching Rate Constants of CCI2 (A1B1and a3B1) by Ketones

CCl2free radicals were produced by dc discharge of CCl4(in Ar). Ground electronic state CCl2radical was electronically excited to A1B1(0,4,0) state with Nd:YAG laser pumpeddye laser at 541.52nm. Experimental quenching data of CCl2(A1B1and a3B1) by several ketones were obtained through observing time resolved fluorescence signal of the excited CCl2radicals, which showed a superposition of two exponential decay components. The state-resolved rate constantsKAandKawere first time acquired by analyzing and dealing with these data by using three-level-model, which was put forward by us.KAandKaincrease on the whole with increasing the number of C-H bonds in ketones.