Solid-liquid phase coexistence of the Lennard-Jones system through phase-switch Monte Carlo simulation

Area of Science:

• Computational physics
• Materials science
• Statistical mechanics

Background:

• Calculating solid-liquid phase coexistence is crucial for understanding material properties.
• Traditional methods often struggle with soft potentials or require simulating complex interfaces.
• The phase-switch Monte Carlo method offers a promising avenue for direct coexistence calculations.

Purpose of the Study:

• To extend the phase-switch Monte Carlo method for calculating solid-liquid phase coexistence in systems with soft potentials.
• To develop an efficient simulation technique that bypasses the need to model interfacial regions.
• To provide a general methodology applicable to various soft matter systems.

Main Methods:

• Extension of the phase-switch Monte Carlo method.
• Introduction of order parameters to define paths between liquid and crystalline phases.
• Utilizing transition matrix methods for biased sampling of both phases.
• Analysis of specific volume probability distributions for coexistence properties.

Main Results:

• Successfully calculated solid-liquid phase coexistence for soft potentials, demonstrated with the Lennard-Jones system.
• Efficiently determined coexistence properties by avoiding direct simulation of the interfacial region.
• Examined finite-size effects and compared them to hard sphere systems.
• Investigated techniques for handling long-range interactions.

Conclusions:

• The extended phase-switch Monte Carlo method provides an efficient and general approach for determining solid-liquid phase coexistence in soft matter systems.
• The methodology offers a robust alternative to traditional simulation techniques, particularly for systems where interfaces are challenging to model.
• This work lays the foundation for applying the method to a broader range of soft potentials and complex materials.