Kinetics, mechanism, and global warming potentials of HFO-1234yf initiated by O molecules and NO radicals: insights from quantum study.

In the present investigation, the oxidation of HFO-1234yf (2,3,3,3-tetrafluoropropene) with O molecule and NO radical is studied by quantum chemical methods. The possible reaction pathways of the titled molecule with O molecule and NO radical are analyzed using M06-2X meta-hybrid density functional with the 6-311++G(d,p) basis set. We have further employed a series of single-point energy calculations by using a potentially high-level couple cluster method with single and double excitations, including perturbative corrections ((CCSD(T)) at the same basis set. The addition reaction of HFO-1234yf with O molecule is initiated by the formation of primary ozonide complex, which leads to the formation of various carbonyl compounds and Criegee intermediates. The calculated energy barriers and thermochemical parameters inferred that decomposition of C˙HOO˙ and CFCFO is slightly more preferred over the formation of CFC˙FOO˙ and CHO. Further, the NO radical addition at α- and β-sits of CFCF〓CH molecule is analyzed in details. The individual and overall rate constants for each reaction pathways are calculated by using canonical transition state theory over the temperature range of 250-450 K. We have observed that the computed rate constants are in good agreement with the available experimental data. Atmospheric lifetimes and global warming potentials of the HFO-1234yf are also reported in this manuscript.