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Title: Assessment of density functional theory based ΔSCF (self-consistent field) and linear response methods for longest wavelength excited states of extended π-conjugated molecular systems

Abstract

Computational investigation of the longest wavelength excitations in a series of cyanines and linear n-acenes is undertaken with the use of standard spin-conserving linear response time-dependent density functional theory (TD-DFT) as well as its spin-flip variant and a ΔSCF method based on the ensemble DFT. The spin-conserving linear response TD-DFT fails to accurately reproduce the lowest excitation energy in these π-conjugated systems by strongly overestimating the excitation energies of cyanines and underestimating the excitation energies of n-acenes. The spin-flip TD-DFT is capable of correcting the underestimation of excitation energies of n-acenes by bringing in the non-dynamic electron correlation into the ground state; however, it does not fully correct for the overestimation of the excitation energies of cyanines, for which the non-dynamic 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 non-dynamic correlation in the ground state of n-acenes 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 π-conjugated systems with the accuracy matching high-level ab initio multireference calculations.

Authors:
 [1];  [2]
  1. Mulliken Center for Theoretical Chemistry, Institut für Physikalische und Theoretische Chemie, Universität Bonn, Beringstr. 4, D-53115 Bonn (Germany)
  2. Institute of Physical and Theoretical Chemistry, Goethe University Frankfurt, Max-von-Laue-Str. 7, D-60438 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, E-mail: mike.filatov@gmail.com, and Huix-Rotllant, Miquel, E-mail: miquel.huix@gmail.com. Assessment of density functional theory based ΔSCF (self-consistent field) and linear response methods for longest wavelength excited states of extended π-conjugated molecular systems. United States: N. p., 2014. Web. doi:10.1063/1.4887087.
Filatov, Michael, E-mail: mike.filatov@gmail.com, & Huix-Rotllant, Miquel, E-mail: miquel.huix@gmail.com. Assessment of density functional theory based ΔSCF (self-consistent field) and linear response methods for longest wavelength excited states of extended π-conjugated molecular systems. United States. doi:10.1063/1.4887087.
Filatov, Michael, E-mail: mike.filatov@gmail.com, and Huix-Rotllant, Miquel, E-mail: miquel.huix@gmail.com. Mon . "Assessment of density functional theory based ΔSCF (self-consistent field) and linear response methods for longest wavelength excited states of extended π-conjugated molecular systems". United States. doi:10.1063/1.4887087.
@article{osti_22308573,
title = {Assessment of density functional theory based ΔSCF (self-consistent field) and linear response methods for longest wavelength excited states of extended π-conjugated molecular systems},
author = {Filatov, Michael, E-mail: mike.filatov@gmail.com and Huix-Rotllant, Miquel, E-mail: miquel.huix@gmail.com},
abstractNote = {Computational investigation of the longest wavelength excitations in a series of cyanines and linear n-acenes is undertaken with the use of standard spin-conserving linear response time-dependent density functional theory (TD-DFT) as well as its spin-flip variant and a ΔSCF method based on the ensemble DFT. The spin-conserving linear response TD-DFT fails to accurately reproduce the lowest excitation energy in these π-conjugated systems by strongly overestimating the excitation energies of cyanines and underestimating the excitation energies of n-acenes. The spin-flip TD-DFT is capable of correcting the underestimation of excitation energies of n-acenes by bringing in the non-dynamic electron correlation into the ground state; however, it does not fully correct for the overestimation of the excitation energies of cyanines, for which the non-dynamic 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 non-dynamic correlation in the ground state of n-acenes 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 π-conjugated systems with the accuracy matching high-level 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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