Stability and Vapor Pressure of Aqueous Aggregates and Aerosols Containing a Monovalent Ion

PEREZ SIRKIN, YAMILA A.; FACTOROVICH, MATÍAS H.; MOLINERO, VALERIA; SCHERLIS, DAMIÁN A.

JOURNAL OF PHYSICAL CHEMISTRY A

AMER CHEMICAL SOC

Año: 2017 vol. 121 p. 2597 - 2602

1089-5639

The incidence of charged particles on the nucleation and the stability of aqueous aggregates and aerosols has been reported more than a century ago. Many studies have been conducted ever since to characterize the stability, structure, and nucleation barrier of ion-water droplets. Most of these studies have focused on the free-energy surface as a functionof cluster size, with an emphasis in the role of ionic charge and radius. This knowledge is fundamental to go beyond the rudimentary ion induced classical nucleation theory. In the present article, we address this problem from a differentperspective, by computing  the vapor pressures of (H$_2$O)$_n$Li$^+$ and (H$_2$O)$_n$Cl$^-$ aggregates using molecular simulations. Our calculations shed light on the structure, the critical size, the range of stability, and the role of ion-water interactions in aqueous clusters. Moreover, theyallow to assess the accuracy of the classical thermodynamic model, highlighting its strengths and weaknesses.