Portal de Periódicos da CAPES

Temperature- and species-dependent quenching of CO B probed by two-photon laser-induced fluorescence using a picosecond laser

2002; American Institute of Physics; Volume: 117; Issue: 7 Linguagem: Inglês

10.1063/1.1493198

1520-9032

Thomas B. Settersten, Andreas Dreizler, Roger L. Farrow,

Advanced Chemical Physics Studies

We report measurements of the temperature- and species-dependent cross sections for the quenching of fluorescence from the B 1Σ+(v=0) state of CO. Cross sections were measured for gas temperatures ranging from 293 K to 1031 K for quenching by H2, N2, O2, CO, H2O, CO2, CH4, He, Ne, Ar, Kr, and Xe. The CO B 1Σ+(v=0) state was populated via two-photon excitation (B 1Σ+←←X 1Σ+), and the B 1Σ+→A 1Π fluorescence was collected. Quenching cross sections were determined from the dependence of the fluorescence-decay rate on quencher-gas pressure. The temperature dependence of the cross sections is well described by a power law for all but the two weakest quenchers, He and Ne.