Ab initio and kinetics study of hydrogen abstraction from 1,1-difluoroethane by hydroxyl radical

The hydrogen abstraction reaction of 1,1-difluoroethane (HFC-152a) with OH radical is investigated by theoretical calculations. Equilibrium geometries and harmonic frequencies are calculated for all stationary points of three hydrogen abstraction reaction pathways at MP2/aug-cc-pVDZ level and the relative energies at CCSD(T)/6-311++G(d,p) level. The rate constants of each channel are evaluated using classical transition state theory with Eckart tunneling corrections over the temperature range of 200-1000 K. The overall rate constants are found to be in reasonable agreement with available experimental values. The results indicate that the α-H abstraction is the major reaction channel in the temperature range.