Algorithm to enforce uniform density in liquid atomistic subdomains with specular boundaries.

Area of Science:

• Computational physics
• Materials science
• Chemical engineering

Background:

• Hybrid atomistic-continuum (HAC) modeling requires proper termination of the atomistic subdomain (ΩA).
• Schwarz domain decomposition method uses specular boundaries, failing to account for periodic forces.
• This leads to spurious density fluctuations at non-periodic boundaries.

Purpose of the Study:

• To develop a novel boundary force algorithm for HAC models.
• To establish a uniform density profile at the non-periodic boundaries of the atomistic subdomain (ΩA).
• To investigate the impact of non-periodic termination on liquid properties.

Main Methods:

• Implementation of a new boundary force algorithm based on force measurements.
• Spatially discretizing the atomistic subdomain (ΩA) for force calculations.
• Analyzing density profiles and liquid properties near the boundary.

Main Results:

• The new algorithm successfully establishes a uniform density profile at non-periodic boundaries.
• Spurious density fluctuations adjacent to specular boundaries are mitigated.
• The method is straightforward to implement and extendable to higher dimensions.

Conclusions:

• The developed boundary force algorithm effectively addresses limitations in HAC modeling.
• Accurate simulation of liquid properties is enhanced by resolving boundary effects.
• This approach offers a robust solution for terminating atomistic domains in hybrid simulations.