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Dynamic transitions in a three dimensional associating lattice gas model
Marcia M Szortyka1, Mauricio Girardi, Vera B Henriques
1Instituto de Física, Universidade Federal do Rio Grande do Sul, Caixa Postal 15051, Porto Alegre 91501-970, RS, Brazil. marcia.szortyka@ufrgs.br
The Journal of Chemical Physics
|April 15, 2010
Summary
This study explores a three dimensional associating lattice gas (ALG) model, revealing two liquid phases and anomalies in structure, density, and diffusion. Dynamic fragile-to-strong transitions are linked to structural order changes.
Area of Science:
- Thermodynamics
- Statistical Mechanics
- Computational Physics
Background:
- Understanding liquid phase behavior and transitions is crucial in condensed matter physics.
- Lattice gas models provide simplified frameworks for studying complex fluid phenomena.
Purpose of the Study:
- To investigate the thermodynamic and dynamic properties of a three dimensional associating lattice gas (ALG) model.
- To explore the relationship between structural order and dynamic transitions in the ALG model.
Main Methods:
- Monte Carlo simulations were employed to study the ALG model.
- The model incorporates a soft core potential and orientational degrees of freedom.
Main Results:
- The ALG model exhibits two coexisting liquid phases due to competing attractive forces and soft core interactions.
- Structural order, density, and diffusion anomalies were observed.
- Order-disorder critical transitions connect the liquid phases.
Conclusions:
- The study links dynamic fragile-to-strong transitions to alterations in structural order.
- The findings offer insights into the complex behavior of associating fluids.
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