Chemiluminescence Spectra and Cross Sections for the Reaction of B(4p 2P) with H2and D2

摘要

Chemiluminescence spectra of electronically excited BH/BD products from thereaction of B(4p 2p) with H2 and D2 have been observed and analyzed. The boron atom reagent was formed by 266 nm multiphoton dissociation of BBr3, and the 4p 2p level was prepared by sequential laser-induced radiative transitions through the 3s 2S level. Chemiluminescence rate constants for production of the A1pi, b3sigma (-), and C'1delta electronic states were determined by comparing the intensities of the product chemiluminescence and the 4p 2P (right arrow) 3s 2S radiative decay of the atomic reagent. From a consideration of the B + H2 yields BH + H adiabatic correlation diagram, it is concluded that formation of the observed products occurs through nonadiabatic transitions from highly excited BH2 potential energy surfaces. Such a model qualitatively explains the large difference in the chemiluminescence cross section between the H2 and D2 reactions.... Boron, Chemiluminescence.