Condensed Matter Physics, 1996, No. 7, p. 89-100, English
DOI:10.5488/CMP.7.89
Title: ASSOCIATIVE REFERENCE MODEL IN THE STATISTICAL THEORY
OF IONIC-AQUEOUS SOLUTIONS
Authors: M.F.Holovko, O.P.Antonevych (Institute for Condensed Matter Physics Ukrainian
National Academy of Sciences, 1 Svientsitskii St., 290011 Lviv, Ukraine)
A new reference model for ionic-aqueous solution is proposed. We
consider a three component hard sphere mixture. One of the species
corresponds to water molecules and includes four short-range
attractive sites, simulating the creation of hydrogen bonds in water.
Other components correspond to cations and anions and
contain one attractive site, which supposes dimerization between them.
The special kind of association between ions and molecules is used for
the description of solvation effects. We suppose, that each site of water
molecules can be only singly bound with ions and each ion can be
bonded with many water sites. The possible number of solvation bonds, that can
be established with the same ions is restricted only by the relationships
between the species diameter. The expression for the unbonded site
concentrations, free energy, and pressure have been obtained. The phase
transition of gas - H-bonds network type, which arises in the model under
consideration for pure water, disappears with increasing of ion fraction.
Comments: Refs. 11, Figs. 6, Tabs. 0.