Tuning range-separated DFT functionals for accurate orbital energy modeling of conjugated molecules

Bhatta, Ram S.; Pellicane, Giuseppe; Tsige, Mesfin

doi:10.1016/j.comptc.2015.07.022

Cited by 20 publications

(16 citation statements)

References 39 publications

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“…The prospect of both linear scaling methods, massively parallel calculations on GPUs instead of CPUs, as well as the optimization 14 or development of new DFT functionals 52 means that large screening and combinatorial design of candidate polymers will become possible. Even if we limited our study to a donor (conjugated 53 ) polymer and to a restricted number of properties to be investigated, a similar screening may be applied to acceptor materials, including small molecules, with a different or wider range of microscopic observables.…”

Section: Discussionmentioning

confidence: 99%

Toward the Rational Design of Organic Solar Photovoltaics: Application of Molecular Structure Methods to Donor Polymers

et al. 2021

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Conjugated polymers are promising candidates in the design of polymer solar cell materials with suitable electronic properties. Recent studies show that the use of different functional groups as side chain in thiophene-based polymers changes the electronic and conformation structures. Here we design new thiophene-based molecules by replacing the hydrogen attached to the backbone of P3MT with electron-donating and electron-withdrawing groups. We then calculate the HOMO, LUMO, and HOMO–LUMO energy gap to quantify the theoretical merit of the new polymers as solar absorbers and their inter-ring torsional potential to understand their suitability to link together in high conductivity, extended conjugated systems. Calculations are done with first-principles density functional theory (DFT), implemented using B3LYP with dispersion function and 6-31G(d,p) as basis set. Our results show that the HOMO–LUMO gap is sensibly lowered by donating groups and we found that the substitution of the hydrogen with −NH 2 , and −F gives an energy gap lower than the energy gap of P3MT. The lowest energy gap was found when substituting with −NH 2 . Electron-withdrawing groups lower the HOMO, with the overall lowest found when −NO 2 is used. −COCl, −CONH 2 , and −Cl give a steric hindrance greater than that of PTB7, which is set as reference. Our calculations show a possible approach to the rational design of donor materials when substituents are inserted systematically in a generic oligomer.

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Section: Discussionmentioning

confidence: 99%

Toward the Rational Design of Organic Solar Photovoltaics: Application of Molecular Structure Methods to Donor Polymers

et al. 2021

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“…Their method has since been used successfully for the quantitative prediction of av ariety of full and partial charge transfer energies. [32][33][34][35] To show the consistency or inconsistencyo ft uned range-separated functionals, we study in particular the performance of TD-wB97Xo no ur criticalh ybrid molecule. As expected and shown in Figure 3, the results of TD-wB97X are parameter-dependent.…”

Section: Resultsmentioning

confidence: 99%

“…have shown that this is not a sufficient condition for a quantitative prediction, but such prediction can be obtained if the range‐separation parameter in a range‐separated hybrid functional is tuned from first principles based on the ionization potential theorem. Their method has since been used successfully for the quantitative prediction of a variety of full and partial charge transfer energies . To show the consistency or inconsistency of tuned range‐separated functionals, we study in particular the performance of TD‐ωB97X on our critical hybrid molecule.…”

Section: Figurementioning

confidence: 99%

Large‐Scale Quantum Many‐Body Perturbation on Spin and Charge Separation in the Excited States of the Synthesized Donor–Acceptor Hybrid PBI–Macrocycle Complex

Ziaei

Bredow

2017

ChemPhysChem

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The reliable calculation of the excited states of charge-transfer (CT) compounds poses a major challenge to the ab initio community because the frequently employed method, time-dependent density functional theory (TD-DFT), massively relies on the underlying density functional, resulting in heavily Hartree-Fock (HF) exchange-dependent excited-state energies. By applying the highly sophisticated many-body perturbation approach, we address the encountered unreliabilities and inconsistencies of not optimally tuned (standard) TD-DFT regarding photo-excited CT phenomena, and present results concerning accurate vertical transition energies and the correct energetic ordering of the CT and the first visible singlet state of a recently synthesized thermodynamically stable large hybrid perylene bisimide-macrocycle complex. This is a large-scale application of the quantum many-body perturbation approach to a chemically relevant CT system, demonstrating the system-size independence of the quality of the many-body-based excitation energies. Furthermore, an optimal tuning of the ωB97X hybrid functional can well reproduce the many-body results, making TD-DFT a suitable choice but at the expense of introducing a range-separation parameter, which needs to be optimally tuned.

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“…This means that it uses a constant of 20% HF exchange for both short and long ranges. CAM-B3LYP [97] and ωB97XD are range-separated hybrid functionals [98] that are suitable for excitation energy calculations and conjugated systems [99]. ωB97XD is a range-separated version of the B97 functional with Grimme's D2 dispersion model (addition of an empirical C6•R -6 dispersion term).…”

Section: Methodsmentioning

confidence: 99%

Non-covalent interactions of cysteine onto C60, C59Si, and C59Ge: a DFT study

Mohammadi

Abdullah

2021

J Mol Model

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The study of intermolecular interactions is of great importance. This study attempted to quantitatively examine the interactions between Cysteine (C3H7NO2S) and fullerene nanocages, C60, in a vacuum. As the frequent introduction of elements as impurities into the structure of nanomaterials can increase the intensity of intermolecular interactions, nanocages doped with silicon and germanium have also been studied as adsorbents C59Si and C59Ge. Quantum mechanical studies of such systems are possible in the density functional theory (DFT) framework. For this purpose, various functionals, such as B3LYP-D3, ωB97XD, and M062X, have been used. One of the most suitable basis functionals for the systems studied in this research is 6-311G (d), which has been used in both optimization calculations and calculations related to wave function analyses. The main part of this work is the study of various analyses that reveal the nature of the intermolecular interactions between the two components introduced above. The results of conceptual DFT, natural bond orbital, non-covalent interactions, and quantum theory of atoms in molecules were consistent and favored physical adsorption in all systems. Germanium had more adsorption energy than other dopants. The HOMO-LUMO energy gaps were as follows: C60: 5.996, C59Si: 5.309, and C59Ge: 5.188 eV at B3LYP-D3/6-311G (d) model chemistry. The adsorption sensitivity increased when an amino acid molecule interacted with doped C60, and this capability could be used to design a nanocarrier to detect Cysteine amino acids.

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Tuning range-separated DFT functionals for accurate orbital energy modeling of conjugated molecules

Cited by 20 publications

References 39 publications

Toward the Rational Design of Organic Solar Photovoltaics: Application of Molecular Structure Methods to Donor Polymers

Toward the Rational Design of Organic Solar Photovoltaics: Application of Molecular Structure Methods to Donor Polymers

Large‐Scale Quantum Many‐Body Perturbation on Spin and Charge Separation in the Excited States of the Synthesized Donor–Acceptor Hybrid PBI–Macrocycle Complex

Non-covalent interactions of cysteine onto C60, C59Si, and C59Ge: a DFT study

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