English (United Kingdom)

https://curated-unify.zendy.io/wp-json/zendy-region/v1/featured_content/oa?rat=en

https://curated-unify.zendy.io/wp-json/zendy-region/v1/highlighted_journal/

Global: Zendy Plus annual

Presents the access of premium content as premium feature

Premium Content

Presents the keyphrase highlighting as premium feature

Keyphrase Highlighting

Presents the summarisation as premium feature

Summarisation

Insights

Presents the pdf analysis as premium feature

PDF Analysis

Presents the zaia usage as premium feature

ZAIA

Global: Zendy Tools annual

Global: Zendy Free Plan

Global: Zendy Tools monthly

Global: Zendy Plus monthly

The effects of size and charge asymmetry on the gas-liquid criticalparameters of a primitive model (PM) of ionic fluids are studied within theframework of the statistical field theory based on the collective variablesmethod. Recently, this approach has enabled us to obtain the correct trends ofthe both critical parameters of the equisize charge-asymmetric PM withoutassuming ionic association. In this paper we focus on the general case of anasymmetric PM characterized by the two parameters: hard-sphere diameter-,$\lambda=\sigma_{+}/\sigma_{-}$ and charge, $z=q_{+}/|q_{-}|$, ratios of thetwo ionic species. We derive an explicit expression for the chemical potentialconjugate to the order parameter which includes the effects of correlations upto the third order. Based on this expression we consider the three versions ofPM: a monovalent size-asymmetric PM ($\lambda\neq 1$, $z=1$), an equisizecharge-asymmetric PM ($\lambda=1$, $z\neq 1$) and a size- and charge-asymmetricPM ($\lambda\neq 1$, $z=2$). Similar to simulations, our theory predicts thatthe critical temperature and the critical density decrease with the increase ofsize asymmetry. Regarding the effects of charge asymmetry, we obtain thecorrect trend of the critical temperature with $z$, while the trend of thecritical density obtained in this approximation is inconsistent withsimulations, as well as with our previous results found in the higher-orderapproximation. We expect that the consideration of the higher-ordercorrelations will lead to the correct trend of the critical density with chargeasymmetry.

Gas-liquid critical parameters of asymmetric models of ionic fluids