Reaction of NO3 radical with benzyl alcohol - A DFT study

Abstract Volatile primary aromatic benzyl alcohol (BzOH) reacts with strong atmospheric oxidants like OH, Cl, NO 3 radicals. The present study elucidates detailed investigation of gas phase reaction mechanisms of benzyl alcohol with NO 3 radicals using density functional theory at M06-2X/6-311+G(d,p) and MPW1K/6-311+G(d,p) levels. The results show that the H-abstraction from methyl group is more energetically favorable with small barrier height. Single-point energy calculations were also performed at the CCSD(T)/6-311+G(d,p) level of theory. The spin state analysis (singlet, triplet) concludes ground state (singlet) reactions are feasible. The reaction force profile along the reaction path is rationalized in terms of structural and electronic rearrangements that take place during the chemical transformation. From the reaction force analysis, it is evident that structural rearrangement plays more dominant role than electronic reordering in this reaction. The calculated rate constant of H-atom abstraction from methyl group of benzyl alcohol with NO 3 radical is 16.72 × 10 −15  cm 3  molecule −1   s −1 , which is in good agreement with experimental study. Overall, NO 3 will replace OH and play a major role in reaction with BzOH during night time.