Phase Diagram of a Reentrant Gel of Patchy Particles Auteur(s): Roldan-Vargas Sandalo, Smallenburg Frank, Kob W., Sciortino Francesco (Article) Publié: The Journal Of Chemical Physics, vol. 139 p.244910 (2013) Texte intégral en Openaccess : Ref HAL: hal-00923977_v1 PMID 24387399 DOI: 10.1063/1.4849115 WoS: 000329191800050 Exporter : BibTex | endNote 16 Citations Résumé: We study the phase diagram of a binary mixture of patchy particles which has been designed to form a reversible gel. For this we perform Monte Carlo and molecular dynamics simulations to investigate the thermodynamics of such a system and compare our numerical results with predictions based on the analytical parameter-free Wertheim theory. We explore a wide range of the temperature-density-composition space that defines the three-dimensional phase diagram of the system. As a result, we delimit the region of thermodynamic stability of the fluid. We find that for a large region of the phase diagram the Wertheim theory is able to give a quantitative description of the system. For higher densities, our simulations show that the system is crystallizing into a BCC structure. Finally, we study the relaxation dynamics of the system by means of the density and temperature dependences of the diffusion coefficient. We show that there exists a density range where the system passes reversibly from a gel to a fluid upon both heating and cooling, encountering neither demixing nor phase separation. |