Comment on Theoretical study of the NO3 radical reaction with CH2ClBr, CH2ICl, CH2BrI, CHCl2Br, and CHClBr2 by I. Alkorta, J. M. C. Plane, J. Elguero, J. Z. Davalos, A. U. Acuna and A. Saiz-Lopez, Phys. Chem. Chem. Phys. 2022, 24, 14365

This comment addresses a systematic error in the potential energy surfaces of the title reactions presented in the original article by Alkorta et al. The NO3 radical has D-3h symmetry in the electronic ground state while the M08HX functional employed in the original article predicts an incorrect C-2v geometry and energy. By combining thermodynamic data for the OH + HNO3 -> H2O + NO3 reaction with spectroscopic data and results from M08HX calculations on HNO3, H2O and the OH radical, the ground state NO3 radical energy is estimated to be 37 kJ mol(-1) lower than reported for the C-2v geometry.

Automated summary

This comment points out a systematic error in the potential energy surfaces of the title reactions discussed in the original article. The M08HX functional used in the original article predicts an incorrect C-2v geometry and energy for the NO3 radical, which actually has D-3h symmetry in its electronic ground state. By combining thermodynamic and spectroscopic data with M08HX calculations, the energy of the ground state NO3 radical is estimated to be 37 kJ mol(-1) lower than previously reported for the C-2v geometry.