Isothermal–isobaric Monte Carlo simulations of liquid lithium using density functional theory

We have performed Monte Carlo simulations of lithium at high temperatures in the isothermal–isobaric and canonical ensembles, using plane-wave density functional theory to provide configurational energies. This is made computationally feasible by the use of an ‘approximate’ empirical potential to generate large Monte Carlo moves with a high likelihood of acceptance. We discuss both simulation results and implementation details. Reasonable results are obtained at high temperatures, though all levels of theory considered systematically overestimate the liquid density.