Electron correlation at the dawn of the 21st century
Werner Kutzelnigg; Pasquale von Herigonte Lehrstuhl für Theoretische Chemie Ruhr-Universität Bochum, D-44780 Bochum, Germany
Abstract
The history and the present state of the treatment of electron correlation is reviewed. For very small atoms or molecules calculations of higher than spectroscopic accuracy are possible. A detailed account for many-electron methods in terms of one-electron basis sets is given with particular attention to the scaling of computer requirements with the size of the molecule. The problems related to the correlation cusp, especially the slow convergence of a basis expansion, as well as their solutions are discussed. The unphysical scaling with the particle number may ...