Studies of Non-Radiating Species in Metal + Oxidant Chemiluminescent Flames

摘要

Chemical production of metastable states of barium oxide in the gas phase have been studied under low pressure flow and molecular beam relaxation free conditions. Optical-optical double resonance excitation of ground state barium oxide has allowed measurements of excited state radiative lifetimes, electronic transition moments and a variety of energy transfer processes. The reactions of Barium with nitrous oxide and nitric oxide are found to produce mostly ground electronic state products, with some production of metastable triplet and singlet states. Electronic transition moments cannot be explained by simple atomic orbital descriptions of molecular states. Rotational relaxation in the first excited singlet pi state of barium oxide is found to be faster than gas kinetic and also exceeds the relaxation rate between lambda components of the pi state. (Author)