Mechanistic and kinetics study of the gas phase reactions of methyltrifluoroacetate with OH radical and Cl atom

Abstract

Abstract Theoretical investigations are carried out on the title reactions by means of ab initio and DFT methods. The optimized geometries, frequencies and minimum energy path are obtained at MPWB1K/6-31+G(d,p) level. Single point energy calculations are performed at MP2 and QCISD(T) levels of theory. Energetics were further refined by calculating the energy of the species with a high level G2(MP2) method. The rate constant of the two reactions are calculated at 298 K and 1 atm using Canonical Transition State Theory (CTST) utilizing the ab initio data obtained during the present study. The rate constant values are found to be 5.5 × 10−14 and 5.9 × 10−14 cm3 molecule−1 s−1, respectively which are in good agreement with the experimental data. Keywords: H-abstractionfluoroesterspotential energy surfaceG2(MP2)canonical transition state theory Acknowledgement One of the authors, BKM thanks the University Grants Commission, New Delhi for providing Dr D. S. K. Post doctoral fellowship. The financial support in the form of a Junior Research Fellowship from CSIR, New Delhi to DB is also acknowledged.