Grand Canonical Monte Carlo (GCMC)
Grand canonical Monte Carlo (GCMC) simulation samples configurations of a system at fixed chemical potential, volume, and temperature, allowing particle numbers to fluctuate and enabling direct calculation of adsorption isotherms, ion distributions, and phase equilibria. As a hard skill it requires setting up force fields or potentials for the material and adsorbate, choosing move types and acceptance criteria, managing equilibration and production run lengths, and post-processing snapshots for structural and thermodynamic quantities. Battery researchers apply GCMC to model electrolyte adsorption in porous electrode materials, compute lithium-ion distribution at electrode-electrolyte interfaces, and screen host materials for ion insertion capacity before committing to synthesis.