1 Department of Physics, Chemistry and Pharmacy, Faculty of Science, SDU 2 Kemisk Institut, Faculty of Science, SDU 3 Kemisk Institut, Faculty of Science, SDU 4 Department of Physics, Chemistry and Pharmacy, Faculty of Science, SDU
Multi-configuration range-separated density-functional theory is extended to the time-dependent regime. An exact variational formulation is derived. The approximation, which consists in combining a long-range Multi-Configuration- Self-Consistent Field (MCSCF) treatment with an adiabatic short-range density-functional (DFT) description, is then considered. The resulting time-dependent multi-configuration short-range DFT (TD-MC-srDFT) model is applied to the calculation of singlet excitation energies in H, Be, and ferrocene, considering both short-range local density (srLDA) and generalized gradient (srGGA) approximations. As expected, when modeling long-range interactions with the MCSCF model instead of the adiabatic Buijse-Baerends density-matrix functional as recently proposed by Pernal [J. Chem. Phys. 136, 184105 (2012)10.1063/1.4712019], the description of both the 1D doubly-excited state in Be and the 11u+ state in the stretched H molecule are improved, although the latter is still significantly underestimated. Exploratory TD-MC-srDFT/GGA calculations for ferrocene yield in general excitation energies at least as good as TD-DFT using the Coulomb attenuated method based on the three-parameter Becke-Lee-Yang-Parr functional (TD-DFT/CAM-B3LYP), and superior to wave-function (TD-MCSCF, symmetry adapted cluster-configuration interaction) and TD-DFT results based on LDA, GGA, and hybrid functionals. © 2013 American Institute of Physics.
Journal of Chemical Physics, 2013, Vol 138
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