REACTION DYNAMICS OF O(D-1) WITH HCN(00(0)V(3))

The quantum state resolved reaction dynamics of HCN(O O-0 upsilon(3)) with O(D-1) atoms were investigated by analyzing the complete product state distributions of OH(X (2) Pi(Omega), upsilon, J) and CN(X (2) Si gma(+), upsilon, J) using laser induced fluorescence (LIF). The influe nce of the CH-stretching mode on the reaction dynamics and different b ranching ratios was inspected by exciting HCN to its first overtone ba nd of the upsilon(3) CH stretch in the 1.5 mu m region. The oxygen ato m in the D-1 state was generated in a laser photolysis of ozone at a w avelength of 266 nm. The measured rotational and vibrational distribut ions of the products were compared with statistical results from phase space theory (PST). Nearly statistical rotational and vibrational dis tributions are obtained for CN(X (2) Sigma(+)) in upsilon=0-3. The rot ational and vibrational distributions of OH(X (2) Pi(Omega)) are colde r than statistically expected. Insertion of O into the CN bond with su bsequent hydrogen migration seems to be a better characterization of t he the reaction mechanism than an insertion of the oxygen atom into th e CH bond. Direct abstraction of hydrogen to form OH is improbable to describe the molecular process. (C) 1995 American Institute of Physics .