Assessment of density functional theory based ΔSCF (selfconsistent field) and linear response methods for longest wavelength excited states of extended πconjugated molecular systems
Abstract
Computational investigation of the longest wavelength excitations in a series of cyanines and linear nacenes is undertaken with the use of standard spinconserving linear response timedependent density functional theory (TDDFT) as well as its spinflip variant and a ΔSCF method based on the ensemble DFT. The spinconserving linear response TDDFT fails to accurately reproduce the lowest excitation energy in these πconjugated systems by strongly overestimating the excitation energies of cyanines and underestimating the excitation energies of nacenes. The spinflip TDDFT is capable of correcting the underestimation of excitation energies of nacenes by bringing in the nondynamic electron correlation into the ground state; however, it does not fully correct for the overestimation of the excitation energies of cyanines, for which the nondynamic correlation does not seem to play a role. The ensemble DFT method employed in this work is capable of correcting for the effect of missing nondynamic correlation in the ground state of nacenes and for the deficient description of differential correlation effects between the ground and excited states of cyanines and yields the excitation energies of both types of extended πconjugated systems with the accuracy matching highlevel ab initio multireference calculations.
 Authors:
 Mulliken Center for Theoretical Chemistry, Institut für Physikalische und Theoretische Chemie, Universität Bonn, Beringstr. 4, D53115 Bonn (Germany)
 Institute of Physical and Theoretical Chemistry, Goethe University Frankfurt, MaxvonLaueStr. 7, D60438 Frankfurt am Main (Germany)
 Publication Date:
 OSTI Identifier:
 22308573
 Resource Type:
 Journal Article
 Resource Relation:
 Journal Name: Journal of Chemical Physics; Journal Volume: 141; Journal Issue: 2; Other Information: (c) 2014 AIP Publishing LLC; Country of input: International Atomic Energy Agency (IAEA)
 Country of Publication:
 United States
 Language:
 English
 Subject:
 37 INORGANIC, ORGANIC, PHYSICAL AND ANALYTICAL CHEMISTRY; ACCURACY; DENSITY FUNCTIONAL METHOD; ELECTRON CORRELATION; EXCITATION; EXCITED STATES; GROUND STATES; SPIN; SPIN FLIP; WAVELENGTHS
Citation Formats
Filatov, Michael, Email: mike.filatov@gmail.com, and HuixRotllant, Miquel, Email: miquel.huix@gmail.com. Assessment of density functional theory based ΔSCF (selfconsistent field) and linear response methods for longest wavelength excited states of extended πconjugated molecular systems. United States: N. p., 2014.
Web. doi:10.1063/1.4887087.
Filatov, Michael, Email: mike.filatov@gmail.com, & HuixRotllant, Miquel, Email: miquel.huix@gmail.com. Assessment of density functional theory based ΔSCF (selfconsistent field) and linear response methods for longest wavelength excited states of extended πconjugated molecular systems. United States. doi:10.1063/1.4887087.
Filatov, Michael, Email: mike.filatov@gmail.com, and HuixRotllant, Miquel, Email: miquel.huix@gmail.com. Mon .
"Assessment of density functional theory based ΔSCF (selfconsistent field) and linear response methods for longest wavelength excited states of extended πconjugated molecular systems". United States.
doi:10.1063/1.4887087.
@article{osti_22308573,
title = {Assessment of density functional theory based ΔSCF (selfconsistent field) and linear response methods for longest wavelength excited states of extended πconjugated molecular systems},
author = {Filatov, Michael, Email: mike.filatov@gmail.com and HuixRotllant, Miquel, Email: miquel.huix@gmail.com},
abstractNote = {Computational investigation of the longest wavelength excitations in a series of cyanines and linear nacenes is undertaken with the use of standard spinconserving linear response timedependent density functional theory (TDDFT) as well as its spinflip variant and a ΔSCF method based on the ensemble DFT. The spinconserving linear response TDDFT fails to accurately reproduce the lowest excitation energy in these πconjugated systems by strongly overestimating the excitation energies of cyanines and underestimating the excitation energies of nacenes. The spinflip TDDFT is capable of correcting the underestimation of excitation energies of nacenes by bringing in the nondynamic electron correlation into the ground state; however, it does not fully correct for the overestimation of the excitation energies of cyanines, for which the nondynamic correlation does not seem to play a role. The ensemble DFT method employed in this work is capable of correcting for the effect of missing nondynamic correlation in the ground state of nacenes and for the deficient description of differential correlation effects between the ground and excited states of cyanines and yields the excitation energies of both types of extended πconjugated systems with the accuracy matching highlevel ab initio multireference calculations.},
doi = {10.1063/1.4887087},
journal = {Journal of Chemical Physics},
number = 2,
volume = 141,
place = {United States},
year = {Mon Jul 14 00:00:00 EDT 2014},
month = {Mon Jul 14 00:00:00 EDT 2014}
}

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