TY  - JOUR
A1  - Körzdörfer, Thomas
A1  - Parrish, Robert M.
A1  - Sears, John S.
A1  - Sherrill, C. David
A1  - Bredas, Jean-Luc
T1  - On the relationship between bond-length alternation and many-electron self-interaction error
JF  - The journal of chemical physics : bridges a gap between journals of physics and journals of chemistr
N2  - Predicting accurate bond-length alternations (BLAs) in long conjugated molecular chains has been a major challenge for electronic-structure theory for many decades. While Hartree-Fock (HF) overestimates BLA significantly, second-order perturbation theory and commonly used density functional theory (DFT) approaches typically underestimate it. Here, we discuss how this failure is related to the many-electron self-interaction error (MSIE), which is inherent to both HF and DFT approaches. We use tuned long-range corrected hybrids to minimize the MSIE for a series of polyenes. The key result is that the minimization of the MSIE alone does not yield accurate BLAs. On the other hand, if the range-separation parameter is tuned to yield accurate BLAs, we obtain a significant MSIE that grows with chain length. Our findings demonstrate that reducing the MSIE is one but not the only important aspect necessary to obtain accurate BLAs from density functional theory.
Y1  - 2012
U6  - https://doi.org/10.1063/1.4752431
SN  - 0021-9606
VL  - 137
IS  - 12
PB  - American Institute of Physics
CY  - Melville
ER  - 
TY  - JOUR
A1  - Sutton, Christopher
A1  - Körzdörfer, Thomas
A1  - Gray, Matthew T.
A1  - Brunsfeld, Max
A1  - Parrish, Robert M.
A1  - Sherrill, C. David
A1  - Sears, John S.
A1  - Bredas, Jean-Luc
T1  - Accurate description of torsion potentials in conjugated polymers using density functionals with reduced self-interaction error
JF  - The journal of chemical physics : bridges a gap between journals of physics and journals of chemistr
N2  - We investigate the torsion potentials in two prototypical pi-conjugated polymers, polyacetylene and polydiacetylene, as a function of chain length using different flavors of density functional theory. Our study provides a quantitative analysis of the delocalization error in standard semilocal and hybrid density functionals and demonstrates how it can influence structural and thermodynamic properties. The delocalization error is quantified by evaluating the many-electron self-interaction error (MESIE) for fractional electron numbers, which allows us to establish a direct connection between the MESIE and the error in the torsion barriers. The use of non-empirically tuned long-range corrected hybrid functionals results in a very significant reduction of the MESIE and leads to an improved description of torsion barrier heights. In addition, we demonstrate how our analysis allows the determination of the effective conjugation length in polyacetylene and polydiacetylene chains.
Y1  - 2014
U6  - https://doi.org/10.1063/1.4863218
SN  - 0021-9606
SN  - 1089-7690
VL  - 140
IS  - 5
PB  - American Institute of Physics
CY  - Melville
ER  - 
TY  - JOUR
A1  - Sun, Haitao
A1  - Ryno, Sean
A1  - Zhong, Cheng
A1  - Ravva, Mahesh Kumar
A1  - Sun, Zhenrong
A1  - Körzdörfer, Thomas
A1  - Bredas, Jean-Luc
T1  - Ionization Energies, Electron Affinities, and Polarization Energies of Organic Molecular Crystals: Quantitative Estimations from a Polarizable Continuum Model (PCM)-Tuned Range-Separated Density Functional Approach
JF  - Journal of chemical theory and computation
N2  - We propose a new methodology for the first principles description of the electronic properties relevant for charge transport in organic molecular crystals. This methodology, which is based on the combination of a nonempirical, optimally tuned range separated hybrid functional with the polarizable continuum model, is applied to a series of eight representative molecular semiconductor crystals. We show that it provides ionization energies, electron affinities, and transport gaps in very good agreement with experimental values, as well as with the results of many-body perturbation theory-within the GW approximation at a fraction of the computational cost. Hence, this approach represents an easily applicable and computationally efficient tool to estimate the gas-to crystal phase shifts of the frontier-orbital quasiparticle energies in organic electronic materials.
Y1  - 2016
U6  - https://doi.org/10.1021/acs.jctc.6b00225
SN  - 1549-9618
SN  - 1549-9626
VL  - 12
SP  - 2906
EP  - 2916
PB  - American Chemical Society
CY  - Washington
ER  -