Combining quantum and classical density functional theory for ion-electron mixtures.

Abstract We combine techniques from quantum and from classical density functional theory (DFT) to describe electron–ion mixtures. For homogeneous systems, we show how to calculate ion–ion and ion–electron correlation functions within Chihara’s quantum hypernetted chain approximation, which we derive within a DFT formulation. We also sketch out how to apply the DFT formulation to inhomogeneous electron–ion mixtures, and use this to study the electron distribution at the liquid–solid interface of Al.