Electronic Energy Partitioning in the Reactions of Metastable Mg*(Pj) Atoms with F2, Cl2, Br2,12, IC1, IBr
نویسنده
چکیده
Chemiluminescent reactions of metastable Mg*(Pj) atoms with F2, Cl2, Br2, I2, IC1, IBr molecules were studied in a beam-gas experiment. For all homonuclear targets the MgX(A FI X X) emission was observed, but for IC1 and IBr reactants the Mgl(A-X) emission was absent and only MgCl(A-X) or MgBr(A-X) spectra were found. In addition, for the I2, IBr, IC1, Br2 reactions, broad pseudocontinua extend from above 400 nm into the infrared. These pseudocontinua are tentatively attributed to the Mgl, MgBr (B' Z X Z) transition. The total attenuation cross sections, chemiluminescence cross sections and quantum yields were measured. The quantum yields are all below 5%. The results are analyzed using information theory. The low yields for the Mg* + F2 system are explained by a barrier in the entrance channel. For other reactions the low yields are most probably caused by predissociation of the MgX*(A n) products.
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