Time-resolved kinetic studies on quenching of [formula omitted] by alkane and alcohol molecules

Abstract

HCCl ( X ˜ 1 A ′ ) radicals were produced by laser photolysis of HCClBr 2 at 213 nm, and were electronically excited to A ˜ 1 A ″ ( 040 ) at 617.97 nm with a dye laser pumped by a Nd:YAG laser. Experimental quenching data of HCCl ( A ˜ 1 A ″ ( 040 ) ) by alkane and alcohol molecules were measured at room temperature (293 K) by observing the time-resolved total fluorescence signals in a cell where the total pressure was 23.0 Torr. It was shown that the quenching rate constant of HCCl ( A ˜ 1 A ″ ( 040 ) ) by alkane molecules increase almost linearly with the number of C–H bonds contained in the homologous molecules. The formation cross-sections of the complexes between HCCl ( A ˜ 1 A ″ ) and quenchers were calculated by means of collision complex model and the attractive forces between the collision partners were considered to play an important role in the quenching processes of HCCl ( A ˜ 1 A ″ ( 040 ) ) by the quenchers studied in this work.