Path-integral analysis of the exchange-correlation energy and potential in density-functional theory: Unpolarized systems.

Abstract

The present work is a demonstration of how the exchange and correlation in density-functional theory can be studied using path-integral techniques. Compact and formally exact expressions for the exchange-correlation functional and potential are derived in terms of the functional integrals. The local density approximation is obtained in the limit of slowly varying density. A perturbative analysis of the exchange-correlation energy and potential via the semiclassical expansion of the effective action is presented. \textcopyright{} 1996 The American Physical Society.