This manuscript describes the further development of the AIOMFAC model to include additional chemical species, such as carbonates and iodine. Using literature thermodynamic data and new experimental observations, the authors derive estimates for the interaction parameters between ionic species and certain organic functional groups. The authors report excellent agreement between model and experimental results for inorganic mixtures, and good agreement with organic mixtures at high humidity. Overall, this work provides the community with a detailed description of the model development and will allow for a broader application of the AIOMFAC model to understanding the thermodynamics of chemically complex systems. It is appropriate for this journal, well-written and can be published with minimal changes, as detailed below.

Specific Comments:

1) On line 279, the authors describe the assumption that CaSO₄ will form a solid. This is reasonable, as the authors point out, for most RH conditions, but likely not cloud forming conditions, where even low solubility species will likely enter solution. How does the assumption of solid formation impact AIOMFAC predictions for CCN activation estimates? What other species are assumed to form solid phases only?

2) Suggest Figure 4 change the x-scale range to better show the relevant data – currently the data points span only 1/5^th or less of the width of the figures, making its hard to judge what the data shows.

3) Figure 5A needs further explanation in the text and/or figure caption – what is  Also, these data are reported at 351 – 366 K – this is very close to the boiling point of water-ethanol, depending on the mixture composition. It’s unclear how to interpret these data and a greater description is necessary.

4) Line 744 – “unlikely realistic” is awkward and confusing phrasing. Please amend.

Technical Points:

• Labels on graphs are generally on the small side and would likely be illegible on printed page.

The manuscript by Yin et al. describes the extension of the AIOMFAC model to iodine and carbonate species. These chemical species are important for sea spray and mineral dust particles in the atmosphere. The extension will play a critical role in future thermodynamic studies on coarse mode particles. Generally, the scientific approach of the manuscript sounds. The output of the developed model agrees well with experimental data when it is available. As the authors mention in the manuscript, experimental data for the chemical species are scarce. I hope that the manuscript will stimulate experimental scientists in the area to conduct high-quality study on the related chemical species, and the authors will update the model parameters in the future when it is needed.

The manuscript is well written, and the topic is within the interest of the readers of the journal. I suggest publication of this manuscript after addressing the

Comments

Table 2

It would be more informative if the authors could add further information about the experimental details of the references (e.g., temperature, range of ionic strength, and experimental method).

Table 3

I understand that determination of weighting factors for this type of study needs to be arbitrary. It would be ideal to have a little bit more detailed descriptions on how the weighting factors have been decided.

L372: ‘Instead, we estimate the interaction parameters for carbonate ions and organic compounds based on those for sulfate ions due to the similar ion size and electric charge:’

The statement might make sense for the Coulombic force. I wonder if the assumption is valid for middle- and short-range forces.

L438: ‘AIOMFAC predictions are substantially lower, by about 0.1 units, than EDB measurements at lower water activity, while they are much better at higher water contents.’

Do the authors have any explanation on this observation?