Experimental Studies of the Chemiluminescent Reactions of Ba（³D）+o,m,p-C₆H₄Cl₂, o,m,p-C₆H₄C1CH₃ Via Molecular Beam

Chemiluminescent reactions of Ba（³D） state prepared by DC discharge with o,m,p-C₆H₄Cl₂, o,m,p-C₆H₄ClCH₃ which resulted in electronically excited states A²∏ , B²∑ andC² ∏ of BaCl were investigated via a molecular beam-gas apparatus. Chemiluminescence spectra, total collision cross sections and relative chemiluminescence cross sections of the reactions were presented in this paper.The results showed that in the reactions of Ba（³D）+o,m,p-C₆H₄C1₂ the relative chemiluminescence cross sections depend on the position of atom Cl on benzene ring. It seems reasonable to assume that the reactions proceeded via two different channels simultaneously: （1） atom Ba attacks directly the C-Cl bond of C₆H₄C1₂ leading to form the BaCl; （2） a valence electron of Ba transfers into a π orbit of benzene ring at first, and then the electron of π orbit of benzene ring transfers into a σ orbit of C-Cl bond via vibrational coupling leading to form the BaCl.