Hunter College, New York

Lundi, 28 novembre 2011,

11h00 Bibliothèque 4e étage,

tour 12 - 13, site Jussieu

The theorems of Time-Dependent Density Functional Theory (TDDFT) hold great promise for the description of real-time electron dynamics in strong and weak fields. In principle, subtle electron correlation effects in processes such as photodissociation dynamics, non-sequential double-ionization, control of electron dynamics for purposes such as selective bond cleavage, etc, can be exactly described. However the approximate functionals available today suffer from three major problems: the lack of memory in density-functional dependence, the need for additional observable functionals to compute quantities such as momentum-distributions, double-ionization probabilities, and the extreme inaccuracy in describing situations where the true wavefunction evolves far from any single-Slater determinant. I will review these difficulties and present examples. A new method has been recently proposed in which electron correlation is evaluated by semiclassical Frozen Gaussian dynamics, that ameliorates all three of these problems. Semiclassical correlation is used to drive the one-body density-matrix time evolution, all other terms of which are computed exactly. I will describe the theory, and present results on some model systems.