Reply to the ‘Comment on “Theoretical study of the NO3 radical reaction with CH2ClBr, CH2ICl, CH2BrI, CHCl2Br, and CHClBr2”’ by C. J. Nielsen and Y. Tang, Phys. Chem. Chem. Phys., 2022, 24, DOI: 10.1039/D2CP03013F

Abstract

In this Reply, we answer the main argument raised in the Comment about the energy of the NO₃ radical and its influence in the reaction profiles of the reaction of the NO₃ radical with CH₂ClBr, CH₂ICl, CH₂BrI, CHCl₂Br, and CHClBr₂ by C. J. Nielsen and Y. Tang. The optimized geometry of the NO₃ radical has been obtained using 49 DFT functionals: 26 functionals predict a minimum with D_3h symmetry and 23 with C_2v symmetry. The former functionals have been used to calculate the thermodynamic values of three reactions (X + HNO₃ → XH + NO₃, X= OH, CH₃ and CCl₃) and compared with experimental data. Those functionals with smaller errors have been used to recalculate the barriers of the reaction of NO₃ with CH₂ClBr, CH₂ICl, CH₂BrI, CHCl₂Br, and CHClBr₂. The results show differences of 10.5 kJ mol⁻¹ when compared to those obtained with the M08HX functional.