Preprints
https://doi.org/10.5194/acp-2021-84
https://doi.org/10.5194/acp-2021-84

  22 Mar 2021

22 Mar 2021

Review status: a revised version of this preprint was accepted for the journal ACP and is expected to appear here in due course.

A Predictive Model for Salt Nanoparticle Formation UsingHeterodimer Stability Calculations

Sabrina Chee1, Kelley Barsanti2, James N. Smith1, and Nanna Myllys1,3 Sabrina Chee et al.
  • 1Department of Chemistry, University of California, Irvine
  • 2Department of Chemical & Environmental Engineering, University of California, Riverside
  • 3Department of Chemistry, University of Jyväskylä

Abstract. Acid–base clusters and stable salt formation are critical drivers of new particle formation events in the atmosphere. In this study, we explore the relationship between J1.5, the theoretically predicted formation rate of clusters larger than 4 acid and 4 base molecules, and acid–base heterodimer stability, a property that is relatively easy to calculate using computational methods. Heterodimer stability as a function of gas-phase acidity, aqueous-phase acidity, heterodimer proton transference, vapor pressure, dipole moment, and polarizability were explored for the salts comprised of sulfuric acid, methanesulfonic acid, and nitric acid with nine bases. The best predictor of heterodimer stability was found to be gas-phase acidity. The relationship between heterodimer stability and J1.5 was analyzed for sulfuric acid salts over a range of monomer concentrations from 105 to 109 molec cm−3 and temperatures from 248 to 348 K. Heterodimer concentration was calculated from heterodimer stability and yielded an expression for predicting  J1.5 for any salt, given approximately equal acid and base monomer concentrations and knowledge of monomer concentration and temperature. This parameterization was tested for the sulfuric acid–ammonia system by comparing the predicted values to experimental data and was found to be accurate within 2 orders of magnitude. We show that one can create a simple parameterization that incorporates the dependence on temperature and monomer concentration on  J1.5 by defining a new term that we call the normalized heterodimer concentration, Φ. A plot of  J1.5 vs. Φ collapses to a single monotonic curve for all weak salts of sulfuric acid, and can be used to accurately estimate  J1.5 in atmospheric models.

Sabrina Chee et al.

Status: closed

Comment types: AC – author | RC – referee | CC – community | EC – editor | CEC – chief editor | : Report abuse
  • RC1: 'Comment on acp-2021-84', Anonymous Referee #1, 25 Mar 2021
  • RC2: 'Review for Chee et al.', Anonymous Referee #2, 05 May 2021

Status: closed

Comment types: AC – author | RC – referee | CC – community | EC – editor | CEC – chief editor | : Report abuse
  • RC1: 'Comment on acp-2021-84', Anonymous Referee #1, 25 Mar 2021
  • RC2: 'Review for Chee et al.', Anonymous Referee #2, 05 May 2021

Sabrina Chee et al.

Sabrina Chee et al.

Viewed

Total article views: 371 (including HTML, PDF, and XML)
HTML PDF XML Total Supplement BibTeX EndNote
267 94 10 371 43 3 3
  • HTML: 267
  • PDF: 94
  • XML: 10
  • Total: 371
  • Supplement: 43
  • BibTeX: 3
  • EndNote: 3
Views and downloads (calculated since 22 Mar 2021)
Cumulative views and downloads (calculated since 22 Mar 2021)

Viewed (geographical distribution)

Total article views: 369 (including HTML, PDF, and XML) Thereof 369 with geography defined and 0 with unknown origin.
Country # Views %
  • 1
1
 
 
 
 

Cited

Latest update: 01 Aug 2021
Download
Short summary
We explored molecular properties affecting atmospheric particle formation efficiency and derived a parameterization between particle formation rate and heterodimer concentration, which showed good agreement to previously reported experimental data. Considering the simplicity of calculating heterodimer concentration, this approach has potential to improve estimates of global cloud condensation nuclei in models that are limited by the computational expense of calculating particle formation rate.
Altmetrics