Atmospheric chemistry of the self-reaction of HO2 radicals: stepwise mechanism versus one-step process in the presence of (H2O)n (n = 1–3) clusters

In the incorporation of the catalyst (H2O)n (n = 1–3) into the HO2 + HO2 → H2O2 + 3O2 reaction, the catalytic effect of water, water dimers and water trimers is mainly derived from the contribution of a single water vapor molecule by a stepwise route.

The catalytic effect of water, water dimers and water trimers on H2S +3O2formation by the HO2+ HS reaction under tropospheric conditions

Catalyst X (X = H2O, (H2O)2and (H2O)3) is incorporated into the channel of H2S +3O2formation and the catalytic effect of water, water dimers and water trimers is mainly taken from the contribution of a single water vapor molecule.

THE VIBRATIONAL CONSTANTS OF ACETYLENE

On the basis of the work done by Darling and Dennison on the water vapor molecule, the vibrational constants of acetylene are calculated, taking into account the resonance interaction arising from the near equality of the fundamentals ν1 and ν3. Seventeen band centers are known experimentally. The band centers depend on the 10 constants χi, χik and γ which are functions of the potential constants. The expressions for the vibrational energies of the band centers are set up, those for interacting doublets or triplets being found by perturbation methods. The 10 constants are determined and the positions of eight bands calculated to check the results. The agreement is very satisfactory. The positions of 10 other bands not yet observed are predicted.