I would like to present to a wide circle of the readers working in
quantum chem- istry and solid-state physics, as, -ell as in other fields
of many-body physics and its interfaces, this book deyoted to density
functional theory written by my colleagues Eugene S. Kryachko and
Eduardo Y. Ludena. Their ways to this theory are rather different
although basically both of them are quantum chemical. Eugene S. Kryachko
came to energy density functional theory from the theory of reduced
density matrices, and Eduardo \. Ludena dewloped earlier the concept of
loges in quantum chemistry. Neyertheless, their earlier interests giw
the possibility to consolidate and formulate energy density functional
theory in a unified and consistent way, in my opinion. Raymond Daudel
Paris ACKNOWLEDGMENTS The authors are indebted to Carl Almbladh, Victor
Va. Antonchenko, John Avery, Richard F. W. Bader, Ulf \on Barth,
Jean-Louis Calais, A. John Coleman, Jens P. Dahl, Robert Donnelly,
Harold Englisch, Robert 1\1. Erdahl, Oswaldo Goscinski, John E.
Harriman, Gintas Kamuntavichius, Illja G. Kaplan, Jaime Keller,
\alentin Khart- siev, Toshikatsu Koga, Per-Olov Lo\ydin, T. Tung
Nguyen-Dang, Ivan Zh. Petkov, Jerome K. Percus, l\lary Beth Ruskai, John
R. Sabin, Zdenek Slanina, \ladimir Shi- rokov, l\lario V. Stoitsov,
Yoram Tal, and \Vaitao Yang, who in one way or another, either through
their kind support, help, discussions or valuable comments created the
human and intellectual background which made this book possible.