title: Nonvariational time-dependent multiconfiguration self-consistent field equations for electronic dynamics in laser-driven molecules.
abstract: A time-dependent multiconfiguration self-consistent field (TDMCSCF) scheme is developed to describe the time-resolved electron dynamics of a laser-driven many-electron atomic or molecular system, starting directly from the time-dependent Schrodinger equation for the system. This nonvariational formulation aims at the full exploitations of concepts, tools, and facilities of existing, well-developed quantum chemical MCSCF codes. The theory uses, in particular, a unitary representation of time-dependent configuration mixings and orbital transformations. Within a short-time, or adiabatic approximation, the TDMCSCF scheme amounts to a second-order split-operator algorithm involving generically the two noncommuting one-electron and two-electron parts of the time-dependent electronic Hamiltonian. We implement the scheme to calculate the laser-induced dynamics of the two-electron H2 molecule described within a minimal basis, and show how electron correlation is affected by the interaction of the molecule with a strong laser field.
authors.affiliation: Département de Chimie, Université Laval, Québec, Québec G1K 7P4, Canada. tung@chm.ulaval.ca
authors.forename: T Tung
authors.initials: TT
authors.lastname: Nguyen-Dang
authors.forename: Michel
authors.initials: M
authors.lastname: Peters
authors.forename: Sen-Ming
authors.initials: SM
authors.lastname: Wang
authors.forename: Evgueni
authors.initials: E
authors.lastname: Sinelnikov
authors.forename: François
authors.initials: F
authors.lastname: Dion