Theoretical study on the kinetics and branching ratios of the gas phase reactions of 4,4,4-trifluorobutanal (TFB) with OH radical in the temperature range of 250–400 K and atmospheric pressure

Qunatum mechanical calculations are carried out on the reactions of CF3CH2CH2CHO (TFB) with OH radical by means of meta hybrid DFT methods. The geometries of the reactants, reaction complex, products and transition states involved in the reaction pathways are optimized at MPWB1 K level of theory using 6-31G(d,p) basis set. Single point energy calculations are performed at MPWB1 K level using extended 6-311+G(3df,2pd) basis set. Using group balanced Isodesmic reactions enthalpy of formation at 298 K ( Δ f H 298 ° ) of reactant and corresponding products are also estimated for the first time by using G2(MP)2 and CBS-QB3 methods. The hydrogen abstraction rate constant for the title reaction are calculated in the temperature range of 250–400 K and atmospheric pressure using the Canonical Transition State Theory (CTST) including tunneling correction. The percentage contributions of all three reaction channels are also reported within temperature range of 250–400 K and atmospheric pressure.