Multiconfiguration methods for time-dependent many-electron dynamics

Abstract

A concise overview of time-dependent multiconfiguration methods for the approximate solution of the time-dependent Schrödinger equation for many-electron systems in intense laser fields is presented. In all the methods introduced, the total wave function of the system is written as a linear combination of Slater determinants. The methods can be divided into two classes, one class in which the orbitals used to construct the Slater determinants are time-independent, and the other class in which the orbitals are time-dependent. The key ideas of these two classes are reviewed, focusing on the scheme used for reducing the number of Slater determinants in the expansion of the wave function. Also described is our recent proposal, in which the number of Slater determinants is not reduced, but the matrix of configuration-interaction coefficients is approximated by a product of three smaller matrices.