Mouyi Weng

Abstract Simulating electrochemical interfaces within density-functional theory (DFT) requires incorporating the electrochemical potential. In practice, this is commonly achieved by varying the number of electrons in the Kohn–Sham equations, leading to grand-canonical DFT calculations. The grand-canonical formalism is related to the canonical ensemble through a Legendre transformation, which maps the energy onto the grand potential while leaving the corresponding atomic forces unchanged.