The associating lattice gas in the presence of interacting solutes

• Autor(a) principal: Girardi, Mauricio
• Data de Publicação: 2015
• Outros Autores: Szortyka, Marcia Martins, Henriques, Vera Bohomoletz, Barbosa, Marcia Cristina Bernardes
• Tipo de documento: Artigo
• Idioma: eng
• Título da fonte: Repositório Institucional da UFRGS
• Texto Completo: http://hdl.handle.net/10183/205551
• topic: Diagramas de fase; Gás de rede; Método de Monte Carlo; Potencial químico; Água; Ligações de hidrogenio

We have investigated the phase diagram of a statistical model for hydrogen-bonding solutions for polar solutes. The structured solvent is represented by an associating lattice gas, which presents anomalous density and liquid-liquid coexistence. Polar solute particles and solvent particles interact attractively, while the solvent-solvent interaction is made directional through bonding arms, which mimic hydrogen bonds. The model behavior is obtained via Monte Carlo simulations in the grand-canonical ensemble, for different sets of parameters. For small solute chemical potential and weak attraction between solute and solvent particles, addition of solute yields a shift in the transition lines of the pure solvent. This is the scenario explored by different authors, in the pursuit of stabilizing the water liquid-liquid coexistence line. However, as we show, in the case of larger solute chemical potentials, or of stronger solute-solvent attractions, new phases may arise.