THE REACTION DYNAMICS OF THE REACTIONS BA+CMH2M+1BR (M=1, 2, 3, 4, 5)

The internal energy distributions of the nascent BaBr products formed in the reactions of Ba+BrR(R=CH3,C2H5,C3H7,C4H9,C5H11) under the singl e collision condition have been first studied by laser-induced fluores cence method. With computer simulations of the experimental spectra, w e obtained the vibrational distributions of the BaBr products, and fou nd that the vibrational excitation and reaction cross-section increase with the number of the carbon atoms in the alkyl radical R. The quasi triatomic LEPS potential of the Ba+CH3 reaction has been deduced rever sely from the experimental results. The dynamics of the reactions Ba+B rR have been studied by the classical trajectory calculations based on the model LEPS potentials. It is concluded that the mass factor and t he C-Br bond strength are the major factors affecting the relationship between vibrational excitation and reaction cross-section with the nu mber of the carbon atoms in the alkyl radical R. Furthermore, we obtai ned all the LEPS potentials of the reactive systems Ba+CmH2m+1 and con firmed its reliability with ab initio calculations.