Laser Applications in Chemistry and Biology: Stimulation, Observation, and Manipulation

AbstractResults from three different types of laser‐based experiments are presented. Using translationally‐excited H atoms, the reaction dynamics of H(2S) + O2(3Σg−) → OH(2Π) + O(3P) was investigated. In order to study the influence of selective reagent translational excitation on the reactivity, absolute reaction cross sections and nascent OH product quantum‐state distributions were measured at different collision energies by means of the laser photolysis/laser‐induced fluorescence (LP/LIF) “pump‐probe” technique. The measured absolute reaction cross sections: σR(1.0eV) = (0.20 ± 0.08) Å2, σR(1.6 eV) = (0.58 ± 0.17) Å2, and σR(1.9 eV) = (0.35 ± 0.14) Å2 clearly confirm the presence of a pronounced maximum in the excitation function (Keßler, K.; Kleinermanns, K. J. Chem. Phys. 1992, 97: 374). The experimental results are compared with results from quasiclassical and recent 3D quantum scattering calculations on ab initio potential energy surfaces.In addition, results from experiments are reported in which two‐dimensional laser light sheet techniques were applied to investigate both the NO formation in a domestic natural gas burner and fuel mixing processes in combustion engines. Ima