Département de chimie moléculaire

A review. The time-dependent extension of d.-functional theory (TDDFT) provides a rigorous formalism allowing the treatment of electronic excitations and excited states. However, just as in traditional (ground-state) d.-functional theory (DFT), the quality of the results depends upon the approxn. used for the unknown exchange-correlation (xc) functional. J. Perdew and K. Schmidt have described the various functionals developed for ground state DFT in terms of a Jacob's ladder, where the rungs correspond to successive levels of approxn. of the xc-functional. Within the adiabatic approxn., these functionals can also be used in TDDFT. However, TDDFT places addnl. demands on the functional that are not typically satisfied by approxns. developed for the ground-state. The simple time-dependent local approxn. already gives remarkably good results for many excited states. However other excitations require more accurate treatment of the xc potential. The authors work on this problem will be summarized in terms of a "Jacob's ladder" adopted to the special needs of applied TDDFT. A review with 72 refs. [on SciFinder(R)]