This manuscript provides a comprehensive theoretical investigation into the ·Cl- -initiated reaction mechanisms of five representative imines. By integrating quantum chemical calculations and kinetic calculations, the study elucidates the reaction pathways, rate constants, and the fate of generated radicals, with particular emphasis on the formation of N-centered radicals and their potential role in nitrosamine formation. This work fills a gap in our understanding of ·Cl-initiated atmospheric oxidation of imines and has important implications for atmospheric chemistry. Overall, the manuscript is well written and clearly presented. In my opinion, it can be accepted for publication after the authors address the following issues.

1. The authors cited many references to introduce the significance sources of ·Cl. I think some significant works also need to read and properly cited in the revised manuscript. (For example, Sci. Technol.2025, 59, 12775; Environ. Sci. Technol. 2025, 59, 9167; Environ. Sci. Technol. 2025, 59, 6155)
2. Missing references for the sentence ‘Daytime ∙Cl concentrations have been reported to reach up to 10⁶ molecule cm^-3’.
3. Computational Details: Missing reference for Molclus program.
4. They should make a bit more clear (in section 2.2 and 2.3) why two different methods (MP2 and M06-2X) and programs (MultiWell and MESMER) were used.
5. Computational Details: please give the parameters used in the long-range transition-state theory with a dispersion force potential.
6. ‘CCSD(T)/6-311+g(2df,2p)’ should be ‘CCSD(T)/6-311+G(2df,2p)’
7. Please mention the pressure in the figure caption.
8. The branching ratio in Table 1 does not appear to be 1. Please check carefully.
9. Page 6, line 170: Missing Figure in SI.
10. Page7, line 220: ‘intramolecular’ should be ‘unimolecular’.
11. Page 10, line 305-309, Missing references.

Xu et al. systematically studied the reaction mechanisms and kinetics of the ·Cl + imines reactions using computational methods. The authors found that imine-derived N-centered radicals exhibits various fates under tropospheric conditions, which significantly differs from the behavior of previously reported amines. This is an interesting study and the paper is a nice addition to the literature on the oxidation of organic nitrogen compounds. I believe this paper is fitting well in ACP. I can recommend publication after the following comments have been addressed.

• I'm confused why two different kinetic simulation software programs are used for the initial and subsequent reactions.
• Not clear to this reviewer which reaction steps were simulated using MultiWell program, and which were simulated using the MESMER program.
• I am missing labels (A) ~ (E) in the Table 1.
• The branch ratio in Table 1 does not appear to be 1.
• The overall reaction rate constants in the abstract are reported with a unit factor of × 10^–11 cm³ molecule⁻¹ s⁻¹, while the same constants in Table 1 use a factor of × 10^–10 cm³ molecule⁻¹ s⁻¹. Please ensure consistency throughout the manuscript.
• Missing reference for Molclus program.
• The parameters used in the long-range transition-state theory were not shown in the manuscript.
• I suggest some important results can be moved from SI to the main text, for example, Figure S3 and S4.