Adiabatic approximation in nonperturbative time-dependent density-functional theory.

Adiabatic approximation of time-dependent density matrix functional response theory.

Time-dependent density matrix functional theory can be formulated in terms of coupled-perturbed response equations, in which a coupling matrix K(omega) features, analogous to the well-known time-dependent density functional theory (TDDFT) case. An adiabatic approximation is needed to solve these equations, but the adiabatic approximation is much more critical since there is not a good "zero ord...

Performance of a nonempirical meta-generalized gradient approximation density functional for excitation energies.

It is known that the adiabatic approximation in time-dependent density functional theory usually provides a good description of low-lying excitations of molecules. In the present work, the capability of the adiabatic nonempirical meta-generalized gradient approximation (meta-GGA) of Tao, Perdew, Staroverov, and Scuseria (TPSS) to describe atomic and molecular excitations is tested. The adiabati...

Charge transfer, double and bond-breaking excitations with time-dependent density matrix functional theory.

Time-dependent density functional theory (TDDFT) in its current adiabatic implementations exhibits three remarkable failures: (a) completely wrong behavior of the excited state surface along a bond-breaking coordinate; (b) lack of doubly excited configurations; (c) much too low charge transfer excitation energies. These TDDFT failure cases are all strikingly exhibited by prototype two-electron ...

Excitation energies of dissociating H2: A problematic case for the adiabatic approximation of time-dependent density functional theory

Time-dependent density functional theory ~TDDFT! is applied for calculation of the excitation energies of the dissociating H2 molecule. The standard TDDFT method of adiabatic local density approximation ~ALDA! totally fails to reproduce the potential curve for the lowest excited singlet Su 1 state of H2. Analysis of the eigenvalue problem for the excitation energies as well as direct derivation...

Time-Dependent One-Body Reduced Density Matrix Functional Theory Adiabatic Approximations and Beyond