Pair density functional theory

The pair density (PD) functional theory is regarded as not only an extension of the density functional theory but also one of the reduced density matrix theories. The main feature of the PD functional theory is that the PD, as a basic variable, essentially contains more information on the electron-electron interaction than the electron density. In order to develop the PD functional theory, there exist two kinds of problems to solve. In this paper, we review our recent approaches about how to tackle with these problems, and show the latest results of the atomic structure calculations for Ne. (c) 2012 Elsevier B.V. All rights reserved.