The chemical equilibrium Br + CH3OH ⇌ HBr + CH2OH (1, −1) has been studied by investigating the kinetics of the forward and reverse reactions. Excimer laser photolysis coupled with Br atom resonance fluorescence detection was used over the temperature range 439−713 K to obtain k 1 = (3.41 ± 0.89) × 109 T 1.5 exp[−(29.93 ± 1.47) kJ mol-1/RT] cm3 mol-1 s-1. The reverse reaction was studied with the fast flow technique, in the temperature range 220−473 K, using laser magnetic resonance for monitoring the CH2OH radicals. Thus, k -1 = (1.20 ± 0.25) × 1012 exp[(3.24 ± 0.44) kJ mol-1/RT] was obtained. The kinetic results were compared with available literature data and possible causes of the deviations were discussed. Kinetic information on the foward and back reactions was combined to obtain the heat of formation for CH2OH. Both second-law and third-law procedures were used in the derivations, giving a recommended value of Δf H°298(CH2OH) = −16.6 ± 1.3 kJ mol-1, which corresponds to the C−H bond dissociation energy of DH°298(H−CH2OH) = 402.3 ± 1.3 kJ mol-1. These thermochemical data obtained from kinetic equilibrium studies agree within the error limits with current photoionization mass spectrometric and ab initio theoretical results.

The absolute yields of the primary products of the reactions of CH2OH with F and Cl atoms and OH radicals were measured in the gas phase at room temperature using a discharge flow apparatus connected to a Far Infrared Laser Magnetic Resonance (FIR‐LMR) spectrometer. Quantitative determinations of the reaction pathways were carried out by employing reference reactions with known product yields. The measurements yielded the branching ratios for the following channels Thus, the main reaction channels were found to be addition of the F, Cl, or OH, respectively, to the CH2 moiety followed by elimination of CO.

The product channels were investigated of the reaction between CH2 and NO in the gas phase at room temperature and near ambient pressure. Mixtures of CH2CO/NO/Ar were photolyzed at λ = 312 nm in a static reactor. The reaction products were analyzed by Fourier transform infrared (FTIR) spectroscopy. The main product (≈︁ 84%) was found to be fulminic acid, HCNO. A second channel (≈︁ 15%) was found to lead to HCN. Other products which were detected include CO, N2O, H2O, HONO, H2CO, and CO2. These are formed (except for the CO from the CH2CO photodissociation) in consecutive reactions of the accompanying H atoms and OH radicals from the HCNO and HCN reaction channels.

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.

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