J. Nolte

Kinetics of the reaction HOCO+O2 in the gas phase

Using the discharge flow method, the kinetics of the gas phase reaction HOCO + O2 products (1) was investigated at room temperature and pressures around p ≈ 2.0 mbar with Far Infrared LaserMagnetic Resonance (FIR-LMR) detection of HOCO, HO2 , and OH. From the measured concentration-versus-time decay profiles of HOCO in the absence and presence of a large excess of O2 , theoverall rate constant of the reaction was found to be k1 (296 K) = (9.9 ±1.5) • 1011 cm3/mol • s. The main reaction channel, which leads to production of HO2 + CO2 , could be established.

Far infrared laser magnetic resonance detection of CHD (X̃ 3A

Far infrared laser magnetic resonance (FIR‐LMR) spectra of the CHD radical in its X3A‘ electronic ground state were observed and assigned. The radicals were generated in the reaction of Na atoms with CHDBr2. LMR spectra were observed using seven laser lines at wavelengths around 100 to 200 μm. The spectra were assigned to six different rotational transitions and the molecular parameters of CHD were determined by a least squares fit. A number of additional transitions, observed using a laser line at λ=184.3 μm but not yet assigned in detail, were attributed to a coupling between the accidentally almost degenerate NKaKc=505 and 413 rotational levels induced by the eab term in the spin–rotation Hamiltonian and by the off‐diagonal components of the hyperfine coupling tensor.Far infrared laser magnetic resonance (FIR-LMR) spectra of the CHD radical in its [ital [tilde X]][sup 3][ital A][double prime] electronic ground state were observed and assigned. The radicals were generated in the reaction of Na atoms with CHDBr[sub 2]. LMR spectra were observed using seven laser lines at wavelengths around 100 to 200 [mu]m. The spectra were assigned to six different rotational transitions and the molecular parameters of CHD were determined by a least squares fit. A number of additional transitions, observed using a laser line at [lambda]=184.3 [mu]m but not yet assigned in detail, were attributed to a coupling between the accidentally almost degenerate [ital N][sub [ital KaKc]]=5[sub 05] and 4[sub 13] rotational levels induced by the [epsilon][sub [ital ab]] term in the spin--rotation Hamiltonian and by the off-diagonal components of the hyperfine coupling tensor.