Mechanistic and kinetic study of the gas-phase reaction of vinyl acetate with ozone

The reaction mechanisms of vinyl acetate with O3 are investigated by performing Density Functional Theory (DFT) calculations as an attempt to investigate the photooxidation reaction of acetate in the atmosphere. The detailed reaction mechanisms are proposed. The potential energy surface profiles (PESs) are constructed. Several products (formaldehyde, heroperoxymethyl formate and formic acetic anhydride) resulting from the gas phase reactions are identified by comparing with the experimental results. The experimentally uncertain dominant product of CH2OO is confirmed to be heroperoxymethyl formate. The experimentally unknown mechanism for the formation of formic acetic anhydride from CH3OCHOO is proposed. Rate constants of the reaction over the temperature range of 200–2000 K are obtained by using Rice–Ramsperger–Kassel–Marcus (RRKM) theory based on the above PES calculations. The rate constants are independent on pressure.

► Mechanism and rate constants for ozonolysis reaction of VAC were investigated.
► Detailed potential energy surface and completed reaction mechanism were proposed.
► Formaldehyde, HPMF and formic acetic anhydride are the major products.
► Experimentally uncertain dominant product of CH2OO is confirmed to be HPMF.
► Unknown mechanism for formation of formic acetic anhydride from IM4 is proposed.