Journal Details

The photo-oxidation reaction of ethyl methacrylate (EMA) initiated by Cl atoms were explored in the Earth’s tropospheric conditions using experimental as well as computational methodologies. The experiments were performed to measure the rate coefficients of the title reaction over the temperature range of 268−363 K by the relative rate method. The rate coefficients for the title reaction were measured relative to 1, 3 butadiene and trans-2-butene. The rate coefficient for the title reaction at 298 K was experimentally measured to be kEMA+ClExp − 298 K = (2.80 ± 0.80) × 10−10 cm3 molecule−1 s−1. The derived Arrhenius expression for the title reaction is kTFEA+ClExp − (268−363K)= (2.32 ± 0.20) × 10−11 exp [(696 ± 54)/T] cm3 molecule−1 s−1. Computational calculations were performed at CCSD(T)//MP2/6-31+G(d, p) level of theory using canonical variational transition state theory (CVT) with small curvature tunneling (SCT) in the temperatures between 200 and 400 K. The degradation mechanism initiated by Cl atoms was proposed for the title reaction based on the qualitative analysis of the products. The important atmospheric parameters such as atmospheric lifetimes, global warming potentials, and photochemical ozone creation potentials, thermochemistry and branching ratios of the test reaction are presented in the manuscript.