Dear Authors,

After carefully reviewing the replies and re-reading the manuscript, I'm ready to accept this manuscript for publication in ACP. Thanks so much for your patience during these difficult times. We opened up 2 weeks ago here at UNC to begin teaching again, including bringing back undergraduates on campus to live in the dorms. Of course, this was a major mistake by the university and now things have been in chaos due to many outbreaks in the dorms and faculty having to move around how they teach again this fall semester. Finally getting back to research items such as handling papers for ACP. In any case, I wanted to make sure you were aware of work that has been done recently on IEPOX-derived SOA from collaborative work involving me and my group. I think these studies may be of relevance to possibly cite in the introduction, but I won't be offended of course if you decide not to include. Please just reply back stating that you did include or preferred not to include. Either way, this paper is ready to be accepted to ACP. Once I hear back from you, I'll immediately accept. Again, no pressure either way, but I only thought these might be of relevance since you focused on monoterpene and sesquiterpene related SOA here.

Thanks so much, Jason Surratt

Papers that relate to phase separation of IEPOX SOA and how this can impede further uptake of IEPOX to make additional SOA:

Riva, M.; Chen, Y.; Zhang, Y.; Lei, Z.; Olson, N. E.; Boyer, H. C.; Narayan, S.; Yee, L. D.; Green, H. S.; Cui, T.; Zhang, Z.; Baumann, K.; Fort, M.; Edgerton, E.; Budisulistiorini, S. H.; Rose, C. A.; Ribeiro, I. O.; e Oliveira, R. L.; dos Santos, E. O.; Machado, C. M. D.; Szopa, S.; Zhao, Y.; Alves, E. G.; de Sá, S. S.; Hu, W.; Knipping, E. M.; Shaw, S. L.; Duvoisin Junior, S.; de Souza, R. A. F.; Palm, B. B.;
Jimenez, J.-L.; Glasius, M.; Goldstein, A. H.; Pye, H. O. T.; Gold, A.; Turpin, B. J.; Vizuete, W.; Martin, S. T.; Thornton, J. A.; Dutcher, C. S.; Ault, A. P.; Surratt, J. D. Increasing Isoprene Epoxydiol-to- Inorganic Sulfate Aerosol Ratio Results in Extensive Conversion of Inorganic Sulfate to Organosulfur Forms: Implications for Aerosol Physicochemical Properties. Environ. Sci. Technol. 2019, 53 (15),
8682−8694.

Zhang, Y.; Chen, Y.; Lei, Z.; Olson, N. E.; Riva, M.; Koss, A. R.;
Zhang, Z.; Gold, A.; Jayne, J. T.; Worsnop, D. R.; Onasch, T. B.;
Kroll, J. H.; Turpin, B. J.; Ault, A. P.; Surratt, J. D. Joint Impacts of
Acidity and Viscosity on the Formation of Secondary Organic Aerosol
from Isoprene Epoxydiols (IEPOX) in Phase Separated Particles. Acs
Earth Space Chem. 2019, 3 (12), 2646−2658.

Olson, N. E.; Lei, Z.; Craig, R. L.; Zhang, Y.; Chen, Y.; Lambe, A. T.; Zhang, Z.; Gold, A.; Surratt, J. D.; Ault, A. P. Reactive Uptake of Isoprene Epoxydiols Increases the Viscosity of the Core of Phase-Separated Aerosol Particles. ACS Earth Space Chem., 2019, 3 (12), 1402-1414.

Zhang, Y.; Chen, Y.; Lambe, A. T.; Olson, N. E.; Lei, Z.; Craig,
R. L.; Zhang, Z.; Gold, A.; Onasch, T. B.; Jayne, J. T.; Worsnop, D. R.;
Gaston, C. J.; Thornton, J. A.; Vizuete, W.; Ault, A. P.; Surratt, J. D.
Effect of the Aerosol-Phase State on Secondary Organic Aerosol
Formation from the Reactive Uptake of Isoprene-Derived Epoxydiols
(IEPOX). Environ. Sci. Technol. Lett. 2018, 5 (3), 167−174.