The extended universal quasichemical (UNIQUAC) model is a thermodynamic model for solutions containing electrolytes and nonelectrolytes. The model is a Gibbs excess function consisting of a Debye–Hückel term and a standard UNIQUAC term. The model only requires binary ion-specific interaction parameters. A unique choice of standard states makes the model able to reproduce solid–liquid, vapor–liq...

• The original equation derived by Hückel is not the common cited in literature Born term included of A concentration-dependent relative permittivity considered In this work we present Hückel’s derivation and considerations, verifying approximations that were done his paper. More complex equations are obtained applying some approximations, these compared to equation. We explore use both a linea...

A Toy Model of an artificial chemistry that treats molecules as graphs was implemented based on a simple Extended Hückel Theory method. Here we describe an extension of the model that models chemical reactions as the result of “collisions”. In order to avoid a possible bias arising from prescribed generic reaction mechanisms, the reactions are simulated in a way that treats the formation and br...

The Debye-Hückel theory describes rigorously the thermal equilibrium of classical Coulomb fluids in the high-temperature β → 0 regime (β denotes the inverse temperature). It is generally believed that the Debye-Hückel theory and the systematic high-temperature expansion provide an adequate description also in the region of small strictly positive values of β > 0. This hypothesis is tested in th...

In this work, we consider a lattice-gas model of charge regulation with electrostatic interactions within the Debye–Hückel level approximation. addition to long-range interactions, incorporates nearest-neighbor for representing non-electrostatic forces between adsorbed ions. The Frumkin–Fowler–Guggenheim isotherm obtained from mean-field analysis accurately reproduces simulation data points.