Visible chemiluminescence in the region 300~900 nm was measured from reactions of F(2P) atoms with CH3Br, CH2Br2 and CHBr2 at various pressures using crossed mol. beam setup. Emissions were observed from vibrationally excited HF(X) and from electronically excited Br2(A or B), BrF(B), CHF(A) and CH(A). The rotational temperature of HF(X) was obtained to be 480 K. The relative vibrational populations of Br2(B) and BrF(B) were solved by computer simulated spectrum. The reaction mechanism was discussed; the primary reaction is mainly the channel of H abstraction, and multistage processes produce electronically activated mols.

Key words: METHANE P, REACTION MECHANISM, FLUORINE, BROMOHYDROCARBON, SPECTROGRAPHIC ANALYSIS, EXCITED STATE, CHEMILUMINESCENCE REACTION, ELECTRON TRANSITION, GAS PHASE REACTION