Effects of the attractive interactions in the thermodynamic, dynamic, and structural anomalies of a two length scale potential

Using molecular dynamic simulations, we study a system of particles interacting through a continuous core-softened potentials consisting of a hard core, a shoulder at closest distances, and an attractive well at further distance. We obtain the pressure–temperature phase diagram of this system for va...

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Bibliographic Details
Authors: Silva, Jonathas Nunes da, Torres, Evy Augusto Salcedo, Oliveira, Alan Barros de, Barbosa, Marcia Cristina Bernardes
Format: article
Status:Published version
Publication Date:2010
Country:Brasil
Institution:Universidade Federal do Rio Grande do Sul (UFRGS)
Repository:Repositório Institucional da UFRGS
Language:English
OAI Identifier:oai:www.lume.ufrgs.br:10183/205081
Online Access:http://hdl.handle.net/10183/205081
Access Level:Open access
Keyword:Diagramas de fase
Difusão
Dinâmica molecular
Propriedades termodinâmicas
Description
Summary:Using molecular dynamic simulations, we study a system of particles interacting through a continuous core-softened potentials consisting of a hard core, a shoulder at closest distances, and an attractive well at further distance. We obtain the pressure–temperature phase diagram of this system for various depths of the tunable attractive well. Since this is a two length scale potential, density, diffusion, and structural anomalies are expected. We show that the effect of increasing the attractive interaction between the molecules is to shrink the region in pressure in which the density and the diffusion anomalies are present. If the attractive forces are too strong, particle will be predominantly in one of the two length scales and no density of diffusion anomaly is observed. The structural anomalous region is present for all the cases.