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arXiv · 2508.10237

FreeBird.jl: An Extensible Toolbox for Simulating Interfacial Phase Equilibria

Ray Yang·Junchi Chen·Douglas Thibodeaux·Robert B. Wexler
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Abstract

We present FreeBird, an extensible Julia-based platform for computational studies of phase equilibria at generic interfaces. The package supports a range of system configurations, from atomistic solid surfaces to coarse-grained lattice$-$gas models, with energies evaluated using classical interatomic potentials or lattice Hamiltonians. Both atomistic and lattice systems accommodate single- or multi-component mixtures with flexibly definable surface and lattice geometries. Implemented sampling algorithms include nested sampling, Wang$-$Landau sampling, Metropolis Monte Carlo, and, for tractable lattice systems, exact enumeration. Leveraging Julia's type hierarchies and multiple dispatch, FreeBird provides a modular interface that allows seamless integration of system definitions, energy evaluators, and sampling schemes. Designed for flexibility, extensibility, and performance, FreeBird offers a versatile framework for exploring the thermodynamics of interfacial phenomena.

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BibTeXRIS

Ray Yang, Junchi Chen, Douglas Thibodeaux, Robert B. Wexler. 2025-08-13. FreeBird.jl: An Extensible Toolbox for Simulating Interfacial Phase Equilibria. https://doi.org/10.1021/acs.jctc.5c01348

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