1
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Ohad G, Hartstein M, Gould T, Neaton JB, Kronik L. Nonempirical Prediction of the Length-Dependent Ionization Potential in Molecular Chains. J Chem Theory Comput 2024. [PMID: 39137361 DOI: 10.1021/acs.jctc.4c00847] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 08/15/2024]
Abstract
The ionization potential of molecular chains is well-known to be a tunable nanoscale property that exhibits clear quantum confinement effects. State-of-the-art methods can accurately predict the ionization potential in the small molecule limit and in the solid-state limit, but for intermediate, nanosized systems prediction of the evolution of the electronic structure between the two limits is more difficult. Recently, optimal tuning of range-separated hybrid functionals has emerged as a highly accurate method for predicting ionization potentials. This was first achieved for molecules using the ionization potential theorem (IPT) and more recently extended to solid-state systems, based on an ansatz that generalizes the IPT to the removal of charge from a localized Wannier function. Here, we study one-dimensional molecular chains of increasing size, from the monomer limit to the infinite polymer limit using this approach. By comparing our results with other localization-based methods and where available with experiment, we demonstrate that Wannier-localization-based optimal tuning is highly accurate in predicting ionization potentials for any chain length, including the nanoscale regime.
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Affiliation(s)
- Guy Ohad
- Department of Molecular Chemistry and Materials Science, Weizmann Institute of Science, Rehovoth 76100, Israel
| | - Michal Hartstein
- Department of Molecular Chemistry and Materials Science, Weizmann Institute of Science, Rehovoth 76100, Israel
| | - Tim Gould
- Queensland Micro- and Nanotechnology Centre, Griffith University, Nathan QLD 4111, Australia
| | - Jeffrey B Neaton
- Department of Physics, University of California, Berkeley, Berkeley, California 94720, United States
- Materials Sciences Division, Lawrence Berkeley National Laboratory, Berkeley, California 94720, United States
- Kavli Energy NanoSciences Institute at Berkeley, University of California, Berkeley, Berkeley, California 94720, United States
| | - Leeor Kronik
- Department of Molecular Chemistry and Materials Science, Weizmann Institute of Science, Rehovoth 76100, Israel
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2
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Manna AK. Thiocarbonyl-Bridged N-Heterotriangulenes for Energy Efficient Triplet Photosensitization: A Theoretical Perspective. Chemphyschem 2024; 25:e202400371. [PMID: 38700483 DOI: 10.1002/cphc.202400371] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/31/2024] [Revised: 05/02/2024] [Accepted: 05/03/2024] [Indexed: 05/05/2024]
Abstract
Structurally-rigid metal-free organic molecules are of high demand for various triplet harvesting applications. However, inefficient intersystem crossing (ISC) due to large singlet-triplet gap (Δ E S - T ${\Delta {E}_{S-T}}$ ) and small spin-orbit coupling (SOC) between lowest excited singlet and triplet often limits their efficiency. Excited electronic states, fluorescence and ISC rates in several thiocarbonyl-bridged N-heterotriangulene ( m ${m}$ S-HTG) with systematically increased thione content (m = ${m=}$ 0-3) are investigated implementing polarization consistent time-dependent optimally-tuned range-separated hybrid. All m ${m}$ S-HTGs are dynamically stable and also thermodynamically feasible to synthesize. Relative energies of several low-lying singlets (S n ${{S}_{n}}$ ) and triplets (T n ${{T}_{n}}$ ), and their excitation nature (i. e.,n π * ${n{\pi }^{^{\ast}}}$ orπ π * ${\pi {\pi }^{^{\ast}}}$ ) and SOC are determined for these m ${m}$ S-HTGs in dichloromethane. Low-energy optical peak displays gradual red-shift with increasing thione content due to relatively smaller electronic gap resulted from greater degree of orbital delocalization. Significantly large SOC due to different orbital-symmetry and heavy-atom effect produces remarkably high ISC rates (k I S C ${{k}_{ISC}}$ ~1012 s-1) for enthalpically favouredS 1 n π * → T 2 ${{S}_{1}\left(n{\pi }^{^{\ast}}\right)\to {T}_{2}}$ (π π * ${\pi {\pi }^{^{\ast}}}$ ) channel in these m ${m}$ S-HTGs, which outcompete radiative fluorescence rates (~108 s-1) even directly from higher lying optically brightπ π * ${\pi {\pi }^{^{\ast}}}$ singlets. Importantly, high energy triplet excitons of ~1.7 eV resulting from such significantly large ISC rates from non-fluorescentS 1 n π * ${{S}_{1}\left(n{\pi }^{^{\ast}}\right)}$ make these thiocarbonylated HTGs ideal candidates for energy efficient triplet harvest including triplet-photosensitization.
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Affiliation(s)
- Arun K Manna
- Department of Chemistry, Indian Institute of Technology Tirupati, 517619, Tirupati, Andhra Pradesh, India
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3
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Dantas Filho RV, de Queiroz TB. Screened optimally tuned range separated hybrid functional for solvated low bandgap molecular systems. J Chem Phys 2024; 161:034109. [PMID: 39007381 DOI: 10.1063/5.0213688] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/12/2024] [Accepted: 06/27/2024] [Indexed: 07/16/2024] Open
Abstract
The description of electronic properties of low bandgap molecular system is often performed by using density functional theory (DFT) and time dependent (TD) DFT calculations with the optimally tuned range-separated hybrid (OT-RSH) functional, as it contains the necessary ingredients to reliably predict charge transfer excitations. However, the range separating parameter (ω) is system-dependent and its optimization, including the chemical environment, is intricate. Refaely-Abramson et al. demonstrated that the gap renormalization in molecular crystals, a ground state property, can be represented by an OT-RSH functional screened by ɛstatic [Phys. Rev. B 88, 081204(R) (2013)], the zero frequency scalar dielectric constant. In this study, we propose the use of an OT-RSH functional screened by the scalar dielectric constant in the high frequency limit (OT-sRSH), ɛ∞, an appropriate constraint for vertical ionization energies or excitations in a dielectric environment. We have performed calculations for S,N-heteroacene derivatives in tetrahydrofuran and dichloromethane. The "unscreened" OT-RSH functional tends to underestimate experimental ionization potentials (IPs) and optical gaps (Egs) by up to 1.5 and 0.5 eV, respectively. In contrast, OT-sRSH functional calculations underestimate IPs and Egs by only 0.4 and 0.2 eV. We also compared the OT-sRSH results to explicitly solvated OT-RSH functional calculations for oligothiophenes in dioxane, benzene in ammonia, and methylene blue in water. We observe that both the approaches perform similarly for weakly interacting intermolecular systems and deviate for solvent-solute interacting systems, as expected. In conclusion, the OT-sRSH functional can describe molecular systems with environmental polarization effects accurately, a step toward describing realistic molecular systems.
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Affiliation(s)
- Reinaldo V Dantas Filho
- Centro de Ciências Naturais e Humanas, Universidade Federal do ABC, Av. dos Estados 5001, 09510-580 Santo André-SP, Brazil
| | - Thiago B de Queiroz
- Centro de Ciências Naturais e Humanas, Universidade Federal do ABC, Av. dos Estados 5001, 09510-580 Santo André-SP, Brazil
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4
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Tedy AM, Manna AK. Nature and energetics of low-lying excited singlets/triplets and intersystem crossing rates in selone analogs of perylenediimide: A theoretical perspective. J Chem Phys 2024; 160:114306. [PMID: 38497472 DOI: 10.1063/5.0200211] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/25/2024] [Accepted: 02/28/2024] [Indexed: 03/19/2024] Open
Abstract
The structural rigidity and chemical diversity of the highly fluorescent perylenediimide (PDI) provide wide opportunities for developing triplet photosensitizers with sufficiently increased energy efficiency. Remarkably high intersystem crossing (ISC) rates with a complete fluorescence turn-off reported recently for several thione analogs of PDI due to substantially large spin-orbit coupling garners huge attention to develop other potential analogs. Here, several selone analogs of PDI, denoted as mSe-PDIs (m = 1-4) with varied Se content and positions, are investigated to provide a comprehensive and comparative picture down the group-16 using density functional theory (DFT) and time-dependent DFT implementing optimally tuned range-separated hybrid in toluene dielectric. All mSe-PDIs are confirmed to be dynamically stable and also thermodynamically feasible to synthesize from their oxygen and thione congeners. The first excited-state singlet (S1) of mSe-PDI with relatively low Se-content (m = 1, 2) is of nπ* character with an expected fluorescence turn-off. Whereas, the ππ* nature of the S1 for 3Se-PDI and 4Se-PDI suggests a possible fluorescence turn-on in the absence of any other active nonradiative deactivation pathways. However, ∼4-6 orders greater ISC rates (∼1012-1014 s-1) than the fluorescence ones (∼108 s-1) for all mSe-PDIs signify highly efficient triplet harvest. Importantly, significantly higher ISC rates for these mSe-PDIs than their thione congeners render them efficient triplet photosensitizers.
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Affiliation(s)
- Annette Mariya Tedy
- Department of Chemistry, Indian Institute of Technology Tirupati, Tirupati, Andhra Pradesh 517619, India
| | - Arun K Manna
- Department of Chemistry, Indian Institute of Technology Tirupati, Tirupati, Andhra Pradesh 517619, India
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5
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Tedy AM, Manna AK. Does the Intersystem Crossing Rate of β-Iodinated Phosphorus Corrole Depend on Iodine Numbers and/or Positions? J Phys Chem A 2023; 127:10118-10127. [PMID: 38011309 DOI: 10.1021/acs.jpca.3c05563] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/29/2023]
Abstract
The heavy-atom effect is known to enhance the intersystem crossing (ISC) in organic molecular systems. Effects of iodine numbers and positions on the ISC rate of a few meso-difluorophenyl substituted β-iodinated phosphorus corroles (PCs) with axially ligated fluorine atoms (mI-FPC; m = 1-4) are studied using a time-dependent optimally tuned range-separated hybrid. Solvent effects are accounted for through a polarizable continuum model with a toluene dielectric. Calculations suggest similar thermodynamic stability for all mI-FPCs and also reproduce the experimentally measured 0-0 energies for some of the freebase phosphorus corrole (FPC) systems studied here. Importantly, our results reveal that all mI-FPCs display 10 times larger ISC rate (∼109 s-1) than the fluorescence rate (∼108 s-1), and the higher ISC rate stems from the improved spin-orbit coupling (SOC) introduced by lighter heteroatoms like central P and biaxial F rather than the I heavy-atom effect. However, an enhanced SOC is found with increasing I content for El-Sayed forbidden ISC channels. Research findings reported in this study unveil the impact of light heteroatoms and heavy atoms in promoting ISC in several iodinated PCs, which help in designing visible-light-driven efficient triplet photosensitizers.
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Affiliation(s)
- Annette Mariya Tedy
- Department of Chemistry and Center for Atomic, Molecular and Optical Sciences & Technologies, Indian Institute of Technology Tirupati, Tirupati, A.P 517619, India
| | - Arun K Manna
- Department of Chemistry and Center for Atomic, Molecular and Optical Sciences & Technologies, Indian Institute of Technology Tirupati, Tirupati, A.P 517619, India
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6
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Liu S, Liu SS, Tang XM, Liu XY, Yang JJ, Cui G, Li L. Solvent effects on the photoinduced charge separation dynamics of directly linked zinc phthalocyanine-perylenediimide dyads: a nonadiabatic dynamics simulation with an optimally tuned screened range-separated hybrid functional. Phys Chem Chem Phys 2023; 25:28452-28464. [PMID: 37846460 DOI: 10.1039/d3cp03517d] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/18/2023]
Abstract
Herein, we have employed a combination of the optimally tuned screened range-separated hybrid (OT-SRSH) functional, the polarizable continuum model (PCM), and nonadiabatic dynamics (NAMD) simulations to investigate the photoinduced dynamics of directly linked donor-acceptor dyads formed using zinc phthalocyanine (ZnPc) and perylenediimide (PDI), in which ZnPc is the donor while PDI is the acceptor. Our simulations aim to analyze the behavior of these dyads upon local excitation of the ZnPc moiety in the gas phase and in benzonitrile. Our findings indicate that the presence of a solvent can significantly influence the excited state dynamics of ZnPc-PDI dyads. Specifically, the polar solvent benzonitrile effectively lowers the vertical excitation energies of the charge transfer (CT) state from ZnPc to PDI. As a result, the energetic order of the locally excited (LE) states of ZnPc and the CT states is reversed compared to the gas phase. Consequently, the photoinduced electron transfer (PET) dynamics from ZnPc to PDI, which is absent in the gas phase, takes place in benzonitrile with a time constant of 10.4 ps. Importantly, our present work not only qualitatively agrees with experimental results but also provides in-depth insights into the underlying mechanisms responsible for the photoinduced dynamics of ZnPc-PDI. Moreover, this study emphasizes the importance of appropriately considering solvent effects in NAMD simulation of organic donor-acceptor systems, taking into account the distinct excited state dynamics observed in the gas phase and benzonitrile. Furthermore, the combination of the OT-SRSH functional, the PCM solvent model, and nonadiabatic dynamics simulations shows promise as a strategy for investigating the complex excited state dynamics of organic donor-acceptor systems in solvents. These findings will be valuable for the future design of novel organic donor-acceptor structures with improved performance.
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Affiliation(s)
- Shuai Liu
- College of Chemistry and Material Science, Sichuan Normal University, Chengdu 610068, China.
| | - Sha-Sha Liu
- College of Chemistry and Material Science, Sichuan Normal University, Chengdu 610068, China.
| | - Xiao-Mei Tang
- College of Chemistry and Material Science, Sichuan Normal University, Chengdu 610068, China.
| | - Xiang-Yang Liu
- College of Chemistry and Material Science, Sichuan Normal University, Chengdu 610068, China.
| | - Jia-Jia Yang
- College of Chemistry and Material Science, Sichuan Normal University, Chengdu 610068, China.
| | - Ganglong Cui
- Key Laboratory of Theoretical and Computational Photochemistry, Ministry of Education, College of Chemistry, Beijing Normal University, Beijing 100875, China
- Hefei National Laboratory, Hefei 230088, China
| | - Laicai Li
- College of Chemistry and Material Science, Sichuan Normal University, Chengdu 610068, China.
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7
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Villot C, Huang T, Lao KU. Accurate prediction of global-density-dependent range-separation parameters based on machine learning. J Chem Phys 2023; 159:044103. [PMID: 37486048 DOI: 10.1063/5.0157340] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/07/2023] [Accepted: 07/03/2023] [Indexed: 07/25/2023] Open
Abstract
In this work, we develop an accurate and efficient XGBoost machine learning model for predicting the global-density-dependent range-separation parameter, ωGDD, for long-range corrected functional (LRC)-ωPBE. This ωGDDML model has been built using a wide range of systems (11 466 complexes, ten different elements, and up to 139 heavy atoms) with fingerprints for the local atomic environment and histograms of distances for the long-range atomic correlation for mapping the quantum mechanical range-separation values. The promising performance on the testing set with 7046 complexes shows a mean absolute error of 0.001 117 a0-1 and only five systems (0.07%) with an absolute error larger than 0.01 a0-1, which indicates the good transferability of our ωGDDML model. In addition, the only required input to obtain ωGDDML is the Cartesian coordinates without electronic structure calculations, thereby enabling rapid predictions. LRC-ωPBE(ωGDDML) is used to predict polarizabilities for a series of oligomers, where polarizabilities are sensitive to the asymptotic density decay and are crucial in a variety of applications, including the calculations of dispersion corrections and refractive index, and surpasses the performance of all other popular density functionals except for the non-tuned LRC-ωPBE. Finally, LRC-ωPBE (ωGDDML) combined with (extended) symmetry-adapted perturbation theory is used in calculating noncovalent interactions to further show that the traditional ab initio system-specific tuning procedure can be bypassed. The present study not only provides an accurate and efficient way to determine the range-separation parameter for LRC-ωPBE but also shows the synergistic benefits of fusing the power of physically inspired density functional LRC-ωPBE and the data-driven ωGDDML model.
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Affiliation(s)
- Corentin Villot
- Department of Chemistry, Virginia Commonwealth University, Richmond, Virginia 23284, USA
| | - Tong Huang
- Department of Chemistry, Virginia Commonwealth University, Richmond, Virginia 23284, USA
| | - Ka Un Lao
- Department of Chemistry, Virginia Commonwealth University, Richmond, Virginia 23284, USA
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8
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Brütting M, Foerster JM, Kümmel S. Understanding Primary Charge Separation in the Heliobacterial Reaction Center. J Phys Chem Lett 2023; 14:3092-3102. [PMID: 36951395 DOI: 10.1021/acs.jpclett.3c00377] [Citation(s) in RCA: 2] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 06/18/2023]
Abstract
The homodimeric reaction center of heliobacteria retains features of the ancestral reaction center and can thus provide insights into the evolution of photosynthesis. Primary charge separation is expected to proceed in a two-step mechanism along either of the two reaction center branches. We reveal the first charge-separation step from first-principles calculations based on time-dependent density functional theory with an optimally tuned range-separated hybrid and ab initio Born-Oppenheimer molecular dynamics: the electron is most likely localized on the electron transfer cofactor 3 (EC3, OH-chlorophyll a), and the hole on the adjacent EC2. Including substantial parts of the surrounding protein environment into the calculations shows that a distinct structural mechanism is decisive for the relative energetic positioning of the electronic excitations: specific charged amino acids in the vicinity of EC3 lower the energy of charge-transfer excitations and thus facilitate efficient charge separation. These results are discussed considering recent experimental insights.
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9
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Froitzheim T, Grimme S, Mewes JM. Either Accurate Singlet-Triplet Gaps or Excited-State Structures: Testing and Understanding the Performance of TD-DFT for TADF Emitters. J Chem Theory Comput 2022; 18:7702-7713. [PMID: 36409831 DOI: 10.1021/acs.jctc.2c00905] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/22/2022]
Abstract
The energy gap between the lowest singlet and triplet excited states (ΔEST) is a key property of thermally activated delayed fluorescence (TADF) emitters, where these states are dominated by charge-transfer (CT) character. Despite its well-known shortcomings concerning CT states, time-dependent density functional theory (TD-DFT) is widely used to predict this gap and study TADF. Moreover, polar CT states exhibit a strong interaction with their molecular environment, which further complicates their computational description. Addressing these two major challenges, this work studies the performance of Tamm-Dancoff-approximated TD-DFT (TDA-DFT) on the recent STGABS27 benchmark set,1 exploring different strategies to include orbital and structural relaxation, as well as dielectric embedding. The results show that the best-performing strategy is to calculate ΔEST at the ground-state structure using functionals with a surprisingly small amount of Fock exchange of ≈10% and without a (complete) solvent model. However, as this approach heavily relies on error cancellation to mimic dielectric relaxation, it is not robust and exhibits large systematic deviations in excited state energies, state characters, and structures. More rigorous approaches, including state-specific solvation, do not share these systematic deviations, but their predicted ΔEST values exhibit larger statistical errors. We thus conclude that for the description of CT states in dielectric environments, none of the tested TDA-DFT methods is competitive with the recently presented ROKS/PCM approach regarding robustness, accuracy, and computational efficiency.
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Affiliation(s)
- Thomas Froitzheim
- Mulliken Center for Theoretical Chemistry, University of Bonn, Beringstr. 4, 53115Bonn, Germany
| | - Stefan Grimme
- Mulliken Center for Theoretical Chemistry, University of Bonn, Beringstr. 4, 53115Bonn, Germany
| | - Jan-Michael Mewes
- Mulliken Center for Theoretical Chemistry, University of Bonn, Beringstr. 4, 53115Bonn, Germany
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10
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Gould T, Dale SG. Poisoning density functional theory with benchmark sets of difficult systems. Phys Chem Chem Phys 2022; 24:6398-6403. [PMID: 35244641 DOI: 10.1039/d2cp00268j] [Citation(s) in RCA: 8] [Impact Index Per Article: 4.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/21/2022]
Abstract
Large benchmark sets like GMTKN55 [Goerigk et al., Phys. Chem. Chem. Phys., 2017, 19, 32184] let us analyse the performance of density functional theory over a diverse range of systems and bonding types. However, assessing over a large and diverse set can miss cases where approaches fail badly, and can give a misleading sense of security. To this end we introduce a series of 'poison' benchmark sets, P30-5, P30-10 and P30-20, comprising systems with up to 5, 10 and 20 atoms, respectively. These sets represent the most difficult-to-model systems in GMTKN55. We expect them to be useful in developing new approximations, identifying weak points in existing ones, and to aid in selecting appropriate DFAs for computational studies involving difficult physics, e.g. catalysis.
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Affiliation(s)
- Tim Gould
- Qld Micro- and Nanotechnology Centre, Griffith University, Nathan, Qld 4111, Australia.
| | - Stephen G Dale
- Qld Micro- and Nanotechnology Centre, Griffith University, Nathan, Qld 4111, Australia.
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11
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Brütting M, Bahmann H, Kümmel S. Hybrid functionals with local range separation: Accurate atomization energies and reaction barrier heights. J Chem Phys 2022; 156:104109. [PMID: 35291795 DOI: 10.1063/5.0082957] [Citation(s) in RCA: 6] [Impact Index Per Article: 3.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/14/2022] Open
Abstract
Range-separated hybrid approximations to the exchange-correlation density functional mix exact and semi-local exchange in a position-dependent manner. In their conventional form, the range separation is controlled by a constant parameter. Turning this constant into a density functional leads to a locally space-dependent range-separation function and thus a more powerful and flexible range-separation approach. In this work, we explore the self-consistent implementation of a local range-separated hybrid, taking into account a one-electron self-interaction correction and the behavior under uniform density scaling. We discuss different forms of the local range-separation function that depend on the electron density, its gradient, and the kinetic energy density. For test sets of atomization energies, reaction barrier heights, and total energies of atoms, we demonstrate that our best model is a clear improvement over common global range-separated hybrid functionals and can compete with density functionals that contain multiple empirical parameters. Promising results for equilibrium bond lengths, harmonic vibrational frequencies, and vertical ionization potentials further underline the potential and flexibility of our approach.
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Affiliation(s)
- Moritz Brütting
- Theoretical Physics IV, University of Bayreuth, 95440 Bayreuth, Germany
| | - Hilke Bahmann
- Physical and Theoretical Chemistry, Saarland University, 66123 Saarbrücken, Germany
| | - Stephan Kümmel
- Theoretical Physics IV, University of Bayreuth, 95440 Bayreuth, Germany
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12
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Hemmingsen LO, Hervir OAJ, Dale SG. Linear fractional charge behavior in density functional theory through dielectric tuning of conductor-like polarizable continuum model. J Chem Phys 2022; 156:014106. [PMID: 34998325 DOI: 10.1063/5.0067685] [Citation(s) in RCA: 2] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/14/2022] Open
Abstract
A property of exact density functional theory is linear fractional charge behavior as electrons are added or removed from a molecule. Typical density functional approximations (DFAs) exhibit delocalization error, which overstabilizes this fractional charge. Conversely, solvent corrections have been shown to erroneously destabilize this fractional charge. This work will show that an implicit solvent correction with a tuned dielectric can be used as an ad hoc correction to offset the delocalizing character of DFAs and achieve linear fractional charge behavior. While desirable, in principle, we find that this linear charge behavior degrades the vertical ionization energies reported by DFAs. Our results reveal that the localizing character of the solvent correction and the Hartree-Fock (HF) exchange offset each other. This helps explain the decreased ratios of HF exchange to DFA exchange in long-range hybrid tuning studies that use a solvent correction.
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Affiliation(s)
- Luke O Hemmingsen
- Research School of Chemistry, Australian National University, Acton 2601, Australia
| | - Oliver A J Hervir
- Research School of Chemistry, Australian National University, Acton 2601, Australia
| | - Stephen G Dale
- Queensland Micro- and Nanotechnology Centre, Griffith University, Nathan 4111, Australia
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13
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Kunze L, Hansen A, Grimme S, Mewes JM. PCM-ROKS for the Description of Charge-Transfer States in Solution: Singlet-Triplet Gaps with Chemical Accuracy from Open-Shell Kohn-Sham Reaction-Field Calculations. J Phys Chem Lett 2021; 12:8470-8480. [PMID: 34449230 DOI: 10.1021/acs.jpclett.1c02299] [Citation(s) in RCA: 10] [Impact Index Per Article: 3.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 06/13/2023]
Abstract
The adiabatic energy gap between the lowest singlet and triplet excited states ΔEST is a central property of thermally activated delayed fluorescence (TADF) emitters. Since these states are dominated by a charge-transfer character, causing strong orbital-relaxation and environmental effects, an accurate prediction of ΔEST is very challenging, even with modern quantum-chemical excited-state methods. Addressing this major challenge, we present an approach that combines spin-unrestricted (UKS) and restricted open-shell Kohn-Sham (ROKS) self-consistent field calculations with a polarizable-continuum model and range-separated hybrid functionals. Tests on a new representative benchmark set of 27 TADF emitters with accurately known ΔEST values termed STGABS27 reveal a robust and unprecedented performance with a mean absolute deviation of only 0.025 eV (∼0.5 kcal/mol) and few deviations greater than 0.05 eV (∼1 kcal/mol), even in electronically challenging cases. Requiring only two geometry optimizations per molecule at the ROKS/UKS level in a compact double-ζ basis, the approach is computationally efficient and can routinely be applied to molecules with more than 100 atoms.
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Affiliation(s)
- Lukas Kunze
- Mulliken Center for Theoretical Chemistry, Institut für Physikalische und Theoretische Chemie, Rheinische Friedrich-Wilhelms Universität Bonn, Beringstraßze 4, 53115 Bonn, Germany
| | - Andreas Hansen
- Mulliken Center for Theoretical Chemistry, Institut für Physikalische und Theoretische Chemie, Rheinische Friedrich-Wilhelms Universität Bonn, Beringstraßze 4, 53115 Bonn, Germany
| | - Stefan Grimme
- Mulliken Center for Theoretical Chemistry, Institut für Physikalische und Theoretische Chemie, Rheinische Friedrich-Wilhelms Universität Bonn, Beringstraßze 4, 53115 Bonn, Germany
| | - Jan-Michael Mewes
- Mulliken Center for Theoretical Chemistry, Institut für Physikalische und Theoretische Chemie, Rheinische Friedrich-Wilhelms Universität Bonn, Beringstraßze 4, 53115 Bonn, Germany
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14
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Gray M, Herbert JM. Simplified tuning of long-range corrected density functionals for use in symmetry-adapted perturbation theory. J Chem Phys 2021; 155:034103. [PMID: 34293871 DOI: 10.1063/5.0059364] [Citation(s) in RCA: 6] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/25/2023] Open
Abstract
Long considered a failure, second-order symmetry-adapted perturbation theory (SAPT) based on Kohn-Sham orbitals, or SAPT0(KS), can be resurrected for semiquantitative purposes using long-range corrected density functionals whose asymptotic behavior is adjusted separately for each monomer. As in other contexts, correct asymptotic behavior can be enforced via "optimal tuning" based on the ionization energy theorem of density functional theory, but the tuning procedure is tedious, expensive for large systems, and comes with a troubling dependence on system size. Here, we show that essentially identical results are obtained using a fast, convenient, and automated tuning procedure based on the size of the exchange hole. In conjunction with "extended" (X)SAPT methods that improve the description of dispersion, this procedure achieves benchmark-quality interaction energies, along with the usual SAPT energy decomposition, without the hassle of system-specific tuning.
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Affiliation(s)
- Montgomery Gray
- Department of Chemistry and Biochemistry, The Ohio State University, Columbus, Ohio 43210, USA
| | - John M Herbert
- Department of Chemistry and Biochemistry, The Ohio State University, Columbus, Ohio 43210, USA
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15
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Carter-Fenk K, Mundy CJ, Herbert JM. Natural Charge-Transfer Analysis: Eliminating Spurious Charge-Transfer States in Time-Dependent Density Functional Theory via Diabatization, with Application to Projection-Based Embedding. J Chem Theory Comput 2021; 17:4195-4210. [PMID: 34189922 DOI: 10.1021/acs.jctc.1c00412] [Citation(s) in RCA: 10] [Impact Index Per Article: 3.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/28/2022]
Abstract
For many types of vertical excitation energies, linear-response time-dependent density functional theory (LR-TDDFT) offers a useful degree of accuracy combined with unrivaled computational efficiency, although charge-transfer excitation energies are often systematically and dramatically underestimated, especially for large systems and those that contain explicit solvent. As a result, low-energy electronic spectra of solution-phase chromophores often contain tens to hundreds of spurious charge-transfer states, making LR-TDDFT needlessly expensive in bulk solution. Intensity borrowing by these spurious states can affect intensities of the valence excitations, altering electronic bandshapes. At higher excitation energies, it is difficult to distinguish spurious charge-transfer states from genuine charge-transfer-to-solvent (CTTS) excitations. In this work, we introduce an automated diabatization that enables fast and effective screening of the CTTS acceptor space in bulk solution. Our procedure introduces "natural charge-transfer orbitals" that provide a means to isolate orbitals that are most likely to participate in a CTTS excitation. Projection of these orbitals onto solvent-centered virtual orbitals provides a criterion for defining the most important solvent molecules in a given excitation and be used as an automated subspace selection algorithm for projection-based embedding of a high-level description of the CTTS state in a lower-level description of its environment. We apply this method to an ab initio molecular dynamics trajectory of I-(aq) and report the lowest-energy CTTS band in the absorption spectrum. Our results are in excellent agreement with the experiment, and only one-third of the water molecules in the I-(H2O)96 simulation cell need to be described with LR-TDDFT to obtain excitation energies that are converged to <0.1 eV. The tools introduced herein will improve the accuracy, efficiency, and usability of LR-TDDFT in solution-phase environments.
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Affiliation(s)
- Kevin Carter-Fenk
- Department of Chemistry and Biochemistry, The Ohio State University, Columbus, Ohio 43210, United States
| | - Christopher J Mundy
- Physical Science Division, Pacific Northwest National Laboratory, Richland, Washington 99352, United States.,Department of Chemical Engineering, University of Washington, Seattle, Washington 98195, United States
| | - John M Herbert
- Department of Chemistry and Biochemistry, The Ohio State University, Columbus, Ohio 43210, United States
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16
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Brütting M, Foerster JM, Kümmel S. Investigating Primary Charge Separation in the Reaction Center of Heliobacterium modesticaldum. J Phys Chem B 2021; 125:3468-3475. [PMID: 33788561 DOI: 10.1021/acs.jpcb.0c10283] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/29/2022]
Abstract
We compute the primary charge separation step in the homodimeric reaction center (RC) of Heliobacterium modesticaldum from first principles. Using time-dependent density functional theory with the optimally tuned range-separated hybrid functional ωPBE, we calculate the excitations of a system comprising the special pair, the adjacent accessory bacteriochlorophylls, and the most relevant parts of the surrounding protein environment. The structure of the excitation spectrum can be rationalized from coupling of the individual bacteriochlorophyll pigments similar to molecular J- and H-aggregates. We find excited states corresponding to forward-charge transfer along the individual branches of the RC of H. modesticaldum. In the spectrum, these are located at an energy between the coupled Qy and Qx transitions. With ab initio Born-Oppenheimer molecular dynamics simulations, we reveal the influence of thermal vibrations on the excited states. The results show that the energy gap between the coupled Qy and the forward-charge transfer excitations is ∼0.4 eV, which we consider to conflict with the concept of a direct transfer mechanism. Our calculations, however, reveal a certain spectral overlap of the forward-charge transfer and the coupled Qx excitations. The reliability and robustness of the results are demonstrated by several numerical tests.
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17
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de Queiroz TB, de Figueroa ER, Coutinho-Neto MD, Maciel CD, Tapavicza E, Hashemi Z, Leppert L. First principles theoretical spectroscopy of methylene blue: Between limitations of time-dependent density functional theory approximations and its realistic description in the solvent. J Chem Phys 2021; 154:044106. [PMID: 33514105 DOI: 10.1063/5.0029727] [Citation(s) in RCA: 9] [Impact Index Per Article: 3.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/14/2022] Open
Abstract
Methylene blue [3,7-Bis(di-methylamino) phenothiazin-5-ium chloride] is a phenothiazine dye with applications as a sensitizer for photodynamic therapy, photoantimicrobials, and dye-sensitized solar cells. Time-dependent density functional theory (TDDFT), based on (semi)local and global hybrid exchange-correlation functionals, fails to correctly describe its spectral features due to known limitations for describing optical excitations of π-conjugated systems. Here, we use TDDFT with a non-empirical optimally tuned range-separated hybrid functional to explore the optical excitations of gas phase and solvated methylene blue. We compute solvated configurations using molecular dynamics and an iterative procedure to account for explicit solute polarization. We rationalize and validate that by extrapolating the optimized range separation parameter to an infinite amount of solvating molecules, the optical gap of methylene blue is well described. Moreover, this method allows us to resolve contributions from solvent-solute intermolecular interactions and dielectric screening. We validate our results by comparing them to first-principles calculations based on the GW+Bethe-Salpeter equation approach and experiment. Vibronic calculations using TDDFT and the generating function method account for the spectra's subbands and bring the computed transition energies to within 0.15 eV of the experimental data. This methodology is expected to perform equivalently well for describing solvated spectra of π-conjugated systems.
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Affiliation(s)
- Thiago B de Queiroz
- Centro de Ciências Naturais e Humanas, Universidade Federal do ABC, Av. dos Estados 5001, 09510-580 Santo André-SP, Brazil
| | - Erick R de Figueroa
- Centro de Ciências Naturais e Humanas, Universidade Federal do ABC, Av. dos Estados 5001, 09510-580 Santo André-SP, Brazil
| | - Maurício D Coutinho-Neto
- Centro de Ciências Naturais e Humanas, Universidade Federal do ABC, Av. dos Estados 5001, 09510-580 Santo André-SP, Brazil
| | - Cleiton D Maciel
- Instituto Federal de Educação, Ciência e Tecnologia de São Paulo, Campus Itaquaquecetuba, Avenida Primeiro de Maio, 500, 08571-050 Itaquaquecetuba-SP, Brazil
| | - Enrico Tapavicza
- Department of Chemistry and Biochemistry, California State University, Long Beach, 1250 Bellflower Boulevard, Long Beach, California 90840, USA
| | - Zohreh Hashemi
- Institute of Physics, University of Bayreuth, Bayreuth 95440, Germany
| | - Linn Leppert
- Institute of Physics, University of Bayreuth, Bayreuth 95440, Germany
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18
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Shee J, Head-Gordon M. Predicting Excitation Energies of Twisted Intramolecular Charge-Transfer States with the Time-Dependent Density Functional Theory: Comparison with Experimental Measurements in the Gas Phase and Solvents Ranging from Hexanes to Acetonitrile. J Chem Theory Comput 2020; 16:6244-6255. [DOI: 10.1021/acs.jctc.0c00635] [Citation(s) in RCA: 13] [Impact Index Per Article: 3.3] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/30/2022]
Affiliation(s)
- James Shee
- Kenneth S. Pitzer Center for Theoretical Chemistry, Department of Chemistry, University of California, Berkeley, California 94720, United States
| | - Martin Head-Gordon
- Kenneth S. Pitzer Center for Theoretical Chemistry, Department of Chemistry, University of California, Berkeley, California 94720, United States
- Chemical Sciences Division, Lawrence Berkeley National Laboratory, Berkeley, California 94720, United States
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19
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Cho E, Coropceanu V, Brédas JL. Electronic Structure of Multicomponent Organic Molecular Materials: Evaluation of Range-Separated Hybrid Functionals. J Chem Theory Comput 2020; 16:3712-3719. [DOI: 10.1021/acs.jctc.0c00138] [Citation(s) in RCA: 14] [Impact Index Per Article: 3.5] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/28/2022]
Affiliation(s)
- Eunkyung Cho
- Department of Chemistry and Biochemistry, The University of Arizona, Tucson, Arizona 85721-0088, United States
- School of Chemistry and Biochemistry, Georgia Institute of Technology, Atlanta, Georgia 30332-0400, United States
| | - Veaceslav Coropceanu
- Department of Chemistry and Biochemistry, The University of Arizona, Tucson, Arizona 85721-0088, United States
- School of Chemistry and Biochemistry, Georgia Institute of Technology, Atlanta, Georgia 30332-0400, United States
| | - Jean-Luc Brédas
- Department of Chemistry and Biochemistry, The University of Arizona, Tucson, Arizona 85721-0088, United States
- School of Chemistry and Biochemistry, Georgia Institute of Technology, Atlanta, Georgia 30332-0400, United States
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20
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Boruah A, Borpuzari MP, Kar R. Performance of Range Separated Density Functional in Solvent Continuum: Tuning Long‐range Hartree–Fock Exchange for Improved Orbital Energies. J Comput Chem 2019; 41:295-304. [DOI: 10.1002/jcc.26101] [Citation(s) in RCA: 6] [Impact Index Per Article: 1.2] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/28/2019] [Revised: 10/10/2019] [Accepted: 10/16/2019] [Indexed: 11/05/2022]
Affiliation(s)
- Abhijit Boruah
- Department of ChemistryDibrugarh University Dibrugarh Assam 786004 India
| | | | - Rahul Kar
- Department of ChemistryDibrugarh University Dibrugarh Assam 786004 India
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21
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Aschebrock T, Kümmel S. Exploring local range separation: The role of spin scaling and one-electron self-interaction. J Chem Phys 2019; 151:154108. [DOI: 10.1063/1.5121731] [Citation(s) in RCA: 6] [Impact Index Per Article: 1.2] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/14/2022] Open
Affiliation(s)
- Thilo Aschebrock
- Theoretical Physics IV, University of Bayreuth, 95440 Bayreuth, Germany
| | - Stephan Kümmel
- Theoretical Physics IV, University of Bayreuth, 95440 Bayreuth, Germany
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22
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Schelter I, Foerster JM, Gardiner AT, Roszak AW, Cogdell RJ, Ullmann GM, de Queiroz TB, Kümmel S. Assessing density functional theory in real-time and real-space as a tool for studying bacteriochlorophylls and the light-harvesting complex 2. J Chem Phys 2019; 151:134114. [DOI: 10.1063/1.5116779] [Citation(s) in RCA: 8] [Impact Index Per Article: 1.6] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 02/04/2023] Open
Affiliation(s)
- Ingo Schelter
- Theoretical Physics IV, University of Bayreuth, Bayreuth, Germany
| | - Johannes M. Foerster
- Theoretical Physics IV and Computational Biochemistry, University of Bayreuth, Bayreuth, Germany
| | | | - Aleksander W. Roszak
- Institute of Molecular, Cell and Systems Biology, University of Glasgow, Glasgow, United Kingdom
| | - Richard J. Cogdell
- Institute of Molecular, Cell and Systems Biology, University of Glasgow, Glasgow, United Kingdom
| | | | | | - Stephan Kümmel
- Theoretical Physics IV, University of Bayreuth, Bayreuth, Germany
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23
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Bhandari S, Dunietz BD. Quantitative Accuracy in Calculating Charge Transfer State Energies in Solvated Molecular Complexes Using a Screened Range Separated Hybrid Functional within a Polarized Continuum Model. J Chem Theory Comput 2019; 15:4305-4311. [DOI: 10.1021/acs.jctc.9b00480] [Citation(s) in RCA: 37] [Impact Index Per Article: 7.4] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/29/2022]
Affiliation(s)
- Srijana Bhandari
- Department of Chemistry & Biochemistry, Kent State University, Kent, Ohio 44242, United States
| | - Barry D. Dunietz
- Department of Chemistry & Biochemistry, Kent State University, Kent, Ohio 44242, United States
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24
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Sachse T, Martínez TJ, Presselt M. On combining the conductor-like screening model and optimally tuned range-separated hybrid density functionals. J Chem Phys 2019; 150:174117. [DOI: 10.1063/1.5064730] [Citation(s) in RCA: 5] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/15/2022] Open
Affiliation(s)
- Torsten Sachse
- Institute of Physical Chemistry, Friedrich-Schiller-University, Helmholtzweg 4, 07743 Jena, Germany
- Leibniz Institute of Photonic Technology (IPHT), Albert-Einstein-Str. 9, 07745 Jena, Germany
| | - Todd J. Martínez
- Department of Chemistry and the PULSE Institute, Stanford University, Stanford, California 94305, USA
- SLAC National Accelerator Laboratory, Menlo Park, California 94025, USA
| | - Martin Presselt
- Institute of Physical Chemistry, Friedrich-Schiller-University, Helmholtzweg 4, 07743 Jena, Germany
- Leibniz Institute of Photonic Technology (IPHT), Albert-Einstein-Str. 9, 07745 Jena, Germany
- Center for Energy and Environmental Chemistry Jena, Humboldtstr. 10, 07743 Jena, Germany
- SciClus GmbH & Co. KG, Moritz-von-Rohr-Str. 1a, 07745 Jena, Germany
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25
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Muchová E, Slavíček P. Beyond Koopmans' theorem: electron binding energies in disordered materials. JOURNAL OF PHYSICS. CONDENSED MATTER : AN INSTITUTE OF PHYSICS JOURNAL 2019; 31:043001. [PMID: 30524069 DOI: 10.1088/1361-648x/aaf130] [Citation(s) in RCA: 5] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 06/09/2023]
Abstract
The topical review focuses on calculating ionization energies (IE), or electronic polarons in quasi-particle terminology, in large disordered systems, e.g. for a solute dissolved in a molecular solvent. The simplest estimate of the ionization energy is provided by one-electron energies in the Hartree-Fock theory, but the calculated quantities are not accurate. Density functional theory as many-body theory provides a principal opportunity for calculating one-electron energies including correlation and relaxation effects, i.e. the true energies of electronic polarons. We argue that such a principal possibility materializes within the concept of optimally tuned range-separated hybrid functionals (OT-RSH). We describe various schemes for optimal tuning. Importantly, the OT-RSH scheme is investigated for systems capped with dielectric continuum, providing a consistent picture on the QM/dielectric boundary. Finally, some limitations and open issues of the OT-RSH approach are addressed.
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Affiliation(s)
- Eva Muchová
- Department of Physical Chemistry, University of Chemistry and Technology, Prague, Czech Republic
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26
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Bhandari S, Cheung MS, Geva E, Kronik L, Dunietz BD. Fundamental Gaps of Condensed-Phase Organic Semiconductors from Single-Molecule Calculations using Polarization-Consistent Optimally Tuned Screened Range-Separated Hybrid Functionals. J Chem Theory Comput 2018; 14:6287-6294. [DOI: 10.1021/acs.jctc.8b00876] [Citation(s) in RCA: 50] [Impact Index Per Article: 8.3] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/28/2022]
Affiliation(s)
- Srijana Bhandari
- Department of Chemistry and Biochemistry, Kent State University, Kent, Ohio 44242, United States
| | - Margaret S. Cheung
- Department of Physics, University of Houston, Houston, Texas 77204, United States
| | - Eitan Geva
- Department of Chemistry, University of Michigan, Ann Arbor, Michigan 48109, United States
| | - Leeor Kronik
- Department of Materials and Interfaces, Weizmann Institute of Science, Rehovoth 76100, Israel
| | - Barry D. Dunietz
- Department of Chemistry and Biochemistry, Kent State University, Kent, Ohio 44242, United States
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27
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Kronik L, Kümmel S. Dielectric Screening Meets Optimally Tuned Density Functionals. ADVANCED MATERIALS (DEERFIELD BEACH, FLA.) 2018; 30:e1706560. [PMID: 29665112 DOI: 10.1002/adma.201706560] [Citation(s) in RCA: 64] [Impact Index Per Article: 10.7] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Subscribe] [Scholar Register] [Received: 11/09/2017] [Revised: 12/19/2017] [Indexed: 06/08/2023]
Abstract
A short overview of recent attempts at merging two independently developed methods is presented. These are the optimal tuning of a range-separated hybrid (OT-RSH) functional, developed to provide an accurate first-principles description of the electronic structure and optical properties of gas-phase molecules, and the polarizable continuum model (PCM), developed to provide an approximate but computationally tractable description of a solvent in terms of an effective dielectric medium. After a brief overview of the OT-RSH approach, its combination with the PCM as a potentially accurate yet low-cost approach to the study of molecular assemblies and solids, particularly in the context of photocatalysis and photovoltaics, is discussed. First, solvated molecules are considered, with an emphasis on the challenge of balancing eigenvalue and total energy trends. Then, it is shown that the same merging of methods can also be used to study the electronic and optical properties of molecular solids, with a similar discussion of the pros and cons. Tuning of the effective scalar dielectric constant as one recent approach that mitigates some of the difficulties in merging the two approaches is considered.
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Affiliation(s)
- Leeor Kronik
- Department of Materials and Interfaces, Weizmann Institute of Science, Rehovoth, 76100, Israel
| | - Stephan Kümmel
- Theoretical Physics IV, Universität Bayreuth, 95440, Bayreuth, Germany
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28
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Neto APV, Machado DFS, Lopes TO, Camargo AJ, de Oliveira HCB. Explicit Aqueous Solvation Treatment of Epinephrine from Car–Parrinello Molecular Dynamics: Effect of Hydrogen Bonding on the Electronic Absorption Spectrum. J Phys Chem B 2018; 122:8439-8450. [DOI: 10.1021/acs.jpcb.8b06110] [Citation(s) in RCA: 4] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/28/2022]
Affiliation(s)
- Arsênio P. V. Neto
- Laboratório de Estrutura Eletrônica e Dinâmica Molecular (LEEDMOL), Instituto de Química, Universidade Federal de Goiás, 70904-970 Brasília, DF, Brazil
| | - Daniel F. Scalabrini Machado
- Laboratório de Estrutura Eletrônica e Dinâmica Molecular (LEEDMOL), Instituto de Química, Universidade Federal de Goiás, 70904-970 Brasília, DF, Brazil
| | - Thiago O. Lopes
- Laboratório de Estrutura Eletrônica e Dinâmica Molecular (LEEDMOL), Instituto de Química, Universidade Federal de Goiás, 70904-970 Brasília, DF, Brazil
| | - Ademir J. Camargo
- Grupo de Química Teórica de Anápolis (GQTEA), Universidade Estadual de Goiás, 75132-903 Anápolis, Goiás, Brazil
| | - Heibbe C. B. de Oliveira
- Laboratório de Estrutura Eletrônica e Dinâmica Molecular (LEEDMOL), Instituto de Química, Universidade Federal de Goiás, 70904-970 Brasília, DF, Brazil
- Laboratório de Estrutura Eletrônica e Dinâmica Molecular (LEEDMOL), Instituto de Química, Universidade de Brasília, 74690-900 Goiânia, Goiás, Brazil
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29
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Manna D, Blumberger J, Martin JML, Kronik L. Prediction of electronic couplings for molecular charge transfer using optimally tuned range-separated hybrid functionals. Mol Phys 2018. [DOI: 10.1080/00268976.2018.1489084] [Citation(s) in RCA: 12] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/28/2022]
Affiliation(s)
- Debashree Manna
- Department of Materials and Interfaces, Weizmann Institute of Science, Rehovoth, Israel
| | - Jochen Blumberger
- Department of Physics and Astronomy, Thomas Young Centre, University College London, London, UK
- Institute for Advanced Study, Technische Universität Munchen, Garching, Germany
| | - Jan M. L. Martin
- Department of Organic Chemistry, Weizmann Institute of Science, Rehovoth, Israel
| | - Leeor Kronik
- Department of Materials and Interfaces, Weizmann Institute of Science, Rehovoth, Israel
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30
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Mewes JM. Modeling TADF in organic emitters requires a careful consideration of the environment and going beyond the Franck-Condon approximation. Phys Chem Chem Phys 2018; 20:12454-12469. [PMID: 29700532 DOI: 10.1039/c8cp01792a] [Citation(s) in RCA: 33] [Impact Index Per Article: 5.5] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/28/2023]
Abstract
The origin of the thermally-activated delayed fluorescence (TADF) of three organic emitters is investigated, focusing on the nature of the lowest excited states, their transition properties, as well as the role of the environment. For this purpose, the algebraic-diagrammatic construction for the polarization propagator at second order of perturbation theory [ADC(2)], time-dependent density-functional theory in the Tamm-Dancoff approximation (TDA) and unrestricted Kohn-Sham DFT in combination with the maximum-overlap method (ΔDFT) are employed. The influence of the dielectric environment is rigorously included using different variants of the polarizable continuum model. The calculations reveal the lowest excited singlet and triplet states of all studied emitters to be dominated by charge-transfer (CT) character already in the most apolar environment corresponding to cyclo-hexane. The dielectric stabilization entails a drastic reduction of the singlet-triplet gaps, increasing the calculated TADF rates by several orders of magnitude. Another ingredient for accurate TADF rates is hidden in the excited-state potential-energy surfaces along the donor-acceptor twisting angle. A presence of large, shallow plateaus in apolar environments causes the transition properties to be governed by thermal fluctuations rather than the minimum-energy geometries. This leads to a large increase of the oscillator strengths, as well as a breakdown of the Franck-Condon approximation. The last ingredient is a small but significant spin-orbit coupling (SOC) between the singlet and triplet CT states, which is traced back to a delocalization of the excitation hole or excited electron of the triplet CT state. Taking into account all of these effects, a reasonable agreement with experimental TADF and fluorescence lifetimes is obtained. For this, it proves to be sufficient to consider only the lowest lying singlet and triplet excited states.
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Affiliation(s)
- Jan-Michael Mewes
- Jan-Michael Mewes, Centre For Theoretical Chemistry and Physics, New-Zealand Institute for Advanced Study, Massey University (Albany), Private Bag 102-904, North Shore Mail Centre, 0632 Auckland, New Zealand.
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31
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Manna AK, Refaely-Abramson S, Reilly AM, Tkatchenko A, Neaton JB, Kronik L. Quantitative Prediction of Optical Absorption in Molecular Solids from an Optimally Tuned Screened Range-Separated Hybrid Functional. J Chem Theory Comput 2018; 14:2919-2929. [DOI: 10.1021/acs.jctc.7b01058] [Citation(s) in RCA: 34] [Impact Index Per Article: 5.7] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/28/2022]
Affiliation(s)
- Arun K. Manna
- Department of Materials and Interfaces, Weizmann Institute of Science, Rehovoth 76100, Israel
| | - Sivan Refaely-Abramson
- Department of Materials and Interfaces, Weizmann Institute of Science, Rehovoth 76100, Israel
| | - Anthony M. Reilly
- School of Chemical Sciences, Dublin City University, Glasnevin, Dublin 9, Ireland
| | - Alexandre Tkatchenko
- Physics and Materials Science Research Unit, University of Luxembourg, L-1511 Luxembourg, Luxembourg
| | - Jeffrey B. Neaton
- Department of Physics, University of California Berkeley, Berkeley, California 94720, United States
- Molecular Foundry, Lawrence Berkeley National Laboratory, Berkeley, California 94720, United States
| | - Leeor Kronik
- Department of Materials and Interfaces, Weizmann Institute of Science, Rehovoth 76100, Israel
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32
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Wong ZC, Fan WY, Chwee TS, Sullivan MB. Using non-empirically tuned range-separated functionals with simulated emission bands to model fluorescence lifetimes. Phys Chem Chem Phys 2018; 19:21046-21057. [PMID: 28748247 DOI: 10.1039/c7cp03418k] [Citation(s) in RCA: 10] [Impact Index Per Article: 1.7] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/21/2022]
Abstract
Fluorescence lifetimes were evaluated using TD-DFT under different approximations for the emitting molecule and various exchange-correlation functionals, such as B3LYP, BMK, CAM-B3LYP, LC-BLYP, M06, M06-2X, M11, PBE0, ωB97, ωB97X, LC-BLYP*, and ωB97X* where the range-separation parameters in the last two functionals were tuned in a non-empirical fashion. Changes in the optimised molecular geometries between the ground and electronically excited states were found to affect the quality of the calculated lifetimes significantly, while the inclusion of vibronic features led to further improvements over the assumption of a vertical electronic transition. The LC-BLYP* functional was found to return the most accurate fluorescence lifetimes with unsigned errors that are mostly within 1.5 ns of experimental values.
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Affiliation(s)
- Z C Wong
- Institute of High Performance Computing, Agency for Science, Technology and Research (A*STAR), 1 Fusionopolis Way, 138632, Singapore. and NUS Graduate School for Integrative Sciences and Engineering, National University of Singapore, 28 Medical Drive, 117456, Singapore
| | - W Y Fan
- Department of Chemistry, National University of Singapore, 3 Science Drive 3, 117543, Singapore
| | - T S Chwee
- Institute of High Performance Computing, Agency for Science, Technology and Research (A*STAR), 1 Fusionopolis Way, 138632, Singapore.
| | - Michael B Sullivan
- Institute of High Performance Computing, Agency for Science, Technology and Research (A*STAR), 1 Fusionopolis Way, 138632, Singapore. and Department of Chemistry, National University of Singapore, 3 Science Drive 3, 117543, Singapore
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33
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Pal AK, Duignan TJ, Autschbach J. Calculation of linear and nonlinear optical properties of azobenzene derivatives with Kohn–Sham and coupled-cluster methods. Phys Chem Chem Phys 2018; 20:7303-7316. [DOI: 10.1039/c7cp08655e] [Citation(s) in RCA: 18] [Impact Index Per Article: 3.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/21/2022]
Abstract
A non-empirically tuned generalized Kohn–Sham functional allows the prediction of accurate low-energy excitation energies and linear polarizabilities. Second hyperpolarizabilities are not improved when compared to coupled-cluster benchmark data.
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Affiliation(s)
- Arun K. Pal
- Department of Chemistry
- University at Buffalo
- State University of New York
- Buffalo
- USA
| | - Thomas J. Duignan
- Department of Chemistry
- University at Buffalo
- State University of New York
- Buffalo
- USA
| | - Jochen Autschbach
- Department of Chemistry
- University at Buffalo
- State University of New York
- Buffalo
- USA
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34
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Rubešová M, Muchová E, Slavíček P. Optimal Tuning of Range-Separated Hybrids for Solvated Molecules with Time-Dependent Density Functional Theory. J Chem Theory Comput 2017; 13:4972-4983. [DOI: 10.1021/acs.jctc.7b00675] [Citation(s) in RCA: 16] [Impact Index Per Article: 2.3] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/30/2022]
Affiliation(s)
- Martina Rubešová
- Department of Physical Chemistry, University of Chemistry and Technology, Technická 5, 16628 Prague, Czech Republic
| | - Eva Muchová
- Department of Physical Chemistry, University of Chemistry and Technology, Technická 5, 16628 Prague, Czech Republic
| | - Petr Slavíček
- Department of Physical Chemistry, University of Chemistry and Technology, Technická 5, 16628 Prague, Czech Republic
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35
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Prediction of the lowest charge-transfer excited-state energy at the donor–acceptor interface in a condensed phase using ground-state DFT calculations with generalized Kohn–Sham functionals. J Mol Model 2017; 23:235. [DOI: 10.1007/s00894-017-3412-y] [Citation(s) in RCA: 7] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/26/2017] [Accepted: 06/29/2017] [Indexed: 10/19/2022]
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36
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Zheng Z, Egger DA, Brédas JL, Kronik L, Coropceanu V. Effect of Solid-State Polarization on Charge-Transfer Excitations and Transport Levels at Organic Interfaces from a Screened Range-Separated Hybrid Functional. J Phys Chem Lett 2017; 8:3277-3283. [PMID: 28666085 DOI: 10.1021/acs.jpclett.7b01276] [Citation(s) in RCA: 54] [Impact Index Per Article: 7.7] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 06/07/2023]
Abstract
We develop a robust approach for the description of the energetics of charge-transfer (CT) excitations and transport levels at organic interfaces based on a screened range-separated hybrid (SRSH) functional. We find that SRSH functionals correctly capture the effect of solid-state electronic polarization on transport gap renormalization and on screening of the electrostatic electron-hole interaction. With respect to calculations based on nonscreened optimally tuned RSH (long-range corrected) functionals, the SRSH-based calculations can be performed for both isolated molecular complexes and systems embedded in a dielectric medium with the same range-separation parameter, which allows a clear physical interpretation of the results in terms of solid-state polarization without any perturbation of the molecular electronic structure. By considering weakly interacting donor/acceptor complexes of pentacene with C60 and poly-3-hexylthiophene (P3HT) with PCBM, we show that this new approach provides CT-state energies that compare very well with experimental data.
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Affiliation(s)
- Zilong Zheng
- School of Chemistry and Biochemistry and Center for Organic Photonics and Electronics, Georgia Institute of Technology , Atlanta, Georgia 30332-0400, United States
| | - David A Egger
- Department of Materials and Interfaces, Weizmann Institute of Science , Rehovoth 76100, Israel
| | - Jean-Luc Brédas
- School of Chemistry and Biochemistry and Center for Organic Photonics and Electronics, Georgia Institute of Technology , Atlanta, Georgia 30332-0400, United States
| | - Leeor Kronik
- Department of Materials and Interfaces, Weizmann Institute of Science , Rehovoth 76100, Israel
| | - Veaceslav Coropceanu
- School of Chemistry and Biochemistry and Center for Organic Photonics and Electronics, Georgia Institute of Technology , Atlanta, Georgia 30332-0400, United States
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37
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Boruah A, Borpuzari MP, Kawashima Y, Hirao K, Kar R. Assessment of range-separated functionals in the presence of implicit solvent: Computation of oxidation energy, reduction energy, and orbital energy. J Chem Phys 2017; 146:164102. [DOI: 10.1063/1.4981529] [Citation(s) in RCA: 15] [Impact Index Per Article: 2.1] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/14/2022] Open
Affiliation(s)
- Abhijit Boruah
- Department of Chemistry, Dibrugarh University, Dibrugarh, Assam 786004, India
| | | | - Yukio Kawashima
- RIKEN Advanced Institute for Computational Science, Kobe, Hyogo 6500047, Japan
| | - Kimihiko Hirao
- RIKEN Advanced Institute for Computational Science, Kobe, Hyogo 6500047, Japan
| | - Rahul Kar
- Department of Chemistry, Dibrugarh University, Dibrugarh, Assam 786004, India
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38
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Raithel D, Baderschneider S, de Queiroz TB, Lohwasser R, Köhler J, Thelakkat M, Kümmel S, Hildner R. Emitting Species of Poly(3-hexylthiophene): From Single, Isolated Chains to Bulk. Macromolecules 2016. [DOI: 10.1021/acs.macromol.6b02077] [Citation(s) in RCA: 29] [Impact Index Per Article: 3.6] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/29/2023]
Affiliation(s)
| | | | - Thiago B. de Queiroz
- Centro
de Ciências Naturais e Humanas, Universidade Federal do ABC, 09510-580, Santo André-SP, Brazil
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39
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Zheng Z, Brédas JL, Coropceanu V. Description of the Charge Transfer States at the Pentacene/C60 Interface: Combining Range-Separated Hybrid Functionals with the Polarizable Continuum Model. J Phys Chem Lett 2016; 7:2616-2621. [PMID: 27338105 DOI: 10.1021/acs.jpclett.6b00911] [Citation(s) in RCA: 29] [Impact Index Per Article: 3.6] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 06/06/2023]
Abstract
Density functional theory (DFT) approaches based on range-separated hybrid functionals are currently methods of choice for the description of the charge-transfer (CT) states in organic donor/acceptor solar cells. However, these calculations are usually performed on small-size donor/acceptor complexes and as result do not account for electronic polarization effects. Here, using a pentacene/C60 complex as a model system, we discuss the ability of long-range corrected (LCR) hybrid functionals in combination with the polarizable continuum model (PCM) to determine the impact of the solid-state environment on the CT states. The CT energies are found to be insensitive to the interactions with the dielectric medium when a conventional time-dependent DFT/PCM (TDDFT/PCM) approach is used. However, a decrease in the energy of the CT state in the framework of LRC functionals can be obtained by using a smaller range-separated parameter when going from an isolated donor/acceptor complex to the solid-state case.
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Affiliation(s)
- Zilong Zheng
- School of Chemistry and Biochemistry and Center for Organic Photonics and Electronics Georgia Institute of Technology, Atlanta, Georgia 30332-0400, United States
| | - Jean-Luc Brédas
- Solar & Photovoltaics Engineering Research Center, Division of Physical Science and Engineering, King Abdullah University of Science and Technology , Thuwal 23955-6900, Saudi Arabia
| | - Veaceslav Coropceanu
- School of Chemistry and Biochemistry and Center for Organic Photonics and Electronics Georgia Institute of Technology, Atlanta, Georgia 30332-0400, United States
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40
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Sun H, Ryno S, Zhong C, Ravva MK, Sun Z, Körzdörfer T, Brédas JL. 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. J Chem Theory Comput 2016; 12:2906-16. [DOI: 10.1021/acs.jctc.6b00225] [Citation(s) in RCA: 96] [Impact Index Per Article: 12.0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/29/2022]
Affiliation(s)
- Haitao Sun
- Solar & Photovoltaics Engineering Research Center, Physical Science and Engineering Division, King Abdullah University of Science and Technology (KAUST), Thuwal 23955-6900, Kingdom of Saudi Arabia
- State
Key Laboratory of Precision Spectroscopy, School of Physics and Materials
Science, East China Normal University (ECNU), Shanghai 200062, People’s Republic of China
| | - Sean Ryno
- Solar & Photovoltaics Engineering Research Center, Physical Science and Engineering Division, King Abdullah University of Science and Technology (KAUST), Thuwal 23955-6900, Kingdom of Saudi Arabia
| | - Cheng Zhong
- Solar & Photovoltaics Engineering Research Center, Physical Science and Engineering Division, King Abdullah University of Science and Technology (KAUST), Thuwal 23955-6900, Kingdom of Saudi Arabia
| | - Mahesh Kumar Ravva
- Solar & Photovoltaics Engineering Research Center, Physical Science and Engineering Division, King Abdullah University of Science and Technology (KAUST), Thuwal 23955-6900, Kingdom of Saudi Arabia
| | - Zhenrong Sun
- State
Key Laboratory of Precision Spectroscopy, School of Physics and Materials
Science, East China Normal University (ECNU), Shanghai 200062, People’s Republic of China
| | | | - Jean-Luc Brédas
- Solar & Photovoltaics Engineering Research Center, Physical Science and Engineering Division, King Abdullah University of Science and Technology (KAUST), Thuwal 23955-6900, Kingdom of Saudi Arabia
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41
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Bois J, Körzdörfer T. How Bond Length Alternation and Thermal Disorder Affect the Optical Excitation Energies of π-Conjugated Chains: A Combined Density Functional Theory and Molecular Dynamics Study. J Chem Theory Comput 2016; 12:1872-82. [DOI: 10.1021/acs.jctc.5b01070] [Citation(s) in RCA: 7] [Impact Index Per Article: 0.9] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/29/2022]
Affiliation(s)
- Juliana Bois
- Institut für Chemie, Universität Potsdam, Karl-Liebknecht-Straße
24-25, 14476 Potsdam, Germany
| | - Thomas Körzdörfer
- Institut für Chemie, Universität Potsdam, Karl-Liebknecht-Straße
24-25, 14476 Potsdam, Germany
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42
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Calculation of low bandgap homopolymers: Comparison of TD-DFT methods with experimental oligomer series. Chem Phys Lett 2016. [DOI: 10.1016/j.cplett.2015.12.059] [Citation(s) in RCA: 26] [Impact Index Per Article: 3.3] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/22/2022]
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43
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Gallandi L, Marom N, Rinke P, Körzdörfer T. Accurate Ionization Potentials and Electron Affinities of Acceptor Molecules II: Non-Empirically Tuned Long-Range Corrected Hybrid Functionals. J Chem Theory Comput 2016; 12:605-14. [DOI: 10.1021/acs.jctc.5b00873] [Citation(s) in RCA: 68] [Impact Index Per Article: 8.5] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/28/2022]
Affiliation(s)
- Lukas Gallandi
- Institut
für Chemie, Universität Potsdam, Karl-Liebknecht-Straße 24-25, 14476 Potsdam, Germany
| | - Noa Marom
- Physics
and Engineering Physics, Tulane University, New Orleans, Louisiana 70118, United States
| | - Patrick Rinke
- COMP/Department
of Applied Physics, Aalto University School of Science, P.O. Box 11100, FI-00076 Aalto, Finland
| | - Thomas Körzdörfer
- Institut
für Chemie, Universität Potsdam, Karl-Liebknecht-Straße 24-25, 14476 Potsdam, Germany
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44
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Mihailovs I, Kampars V, Turovska B, Rutkis M. Rational computing of energy levels for organic electronics: the case of 2-benzylidene-1,3-indandiones. RSC Adv 2016. [DOI: 10.1039/c6ra16456k] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.1] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/15/2022] Open
Abstract
To compute ionization potential and electron affinity (HOMO & LUMO levels by tradition), diffuse functions are redundant, while range-separated hybrid DFT is not always better than B3LYP. Solvent modelling is essential and can be cheap with CPCM.
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Affiliation(s)
- Igors Mihailovs
- Institute of Solid State Physics
- University of Latvia
- Riga
- Latvia
- Institute of Applied Chemistry
| | - Valdis Kampars
- Institute of Applied Chemistry
- Riga Technical University
- Riga
- Latvia
| | | | - Martins Rutkis
- Institute of Solid State Physics
- University of Latvia
- Riga
- Latvia
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45
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Gallandi L, Körzdörfer T. Long-Range Corrected DFT Meets GW: Vibrationally Resolved Photoelectron Spectra from First Principles. J Chem Theory Comput 2015; 11:5391-400. [DOI: 10.1021/acs.jctc.5b00820] [Citation(s) in RCA: 42] [Impact Index Per Article: 4.7] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/28/2022]
Affiliation(s)
- Lukas Gallandi
- Institut für Chemie, Universität Potsdam, Karl-Liebknecht-Straße 24-25, 14476 Potsdam, Germany
| | - Thomas Körzdörfer
- Institut für Chemie, Universität Potsdam, Karl-Liebknecht-Straße 24-25, 14476 Potsdam, Germany
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46
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de Queiroz TB, Kümmel S. Tuned range separated hybrid functionals for solvated low bandgap oligomers. J Chem Phys 2015. [PMID: 26203008 DOI: 10.1063/1.4926468] [Citation(s) in RCA: 39] [Impact Index Per Article: 4.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/14/2022] Open
Abstract
The description of charge transfer excitations has long been a challenge to time dependent density functional theory. The recently developed concept of "optimally tuned range separated hybrid (OT-RSH) functionals" has proven to describe charge transfer excitations accurately in many cases. However, describing solvated or embedded systems is yet a challenge. This challenge is not only computational but also conceptual, because the tuning requires identifying a specific orbital, typically the highest occupied one of the molecule under study. For solvated molecules, this orbital may be delocalized over the solvent. We here demonstrate that one way of overcoming this problem is to use a locally projected self-consistent field diagonalization on an absolutely localized molecular orbital expansion. We employ this approach to determine ionization energies and the optical gap of solvated oligothiophenes, i.e., paradigm low gap systems that are of relevance in organic electronics. Dioxane solvent molecules are explicitly represented in our calculations, and the ambiguities of straightforward parameter tuning in solution are elucidated. We show that a consistent estimate of the optimal range separated parameter (ω) at the limit of bulk solvation can be obtained by gradually extending the solvated system. In particular, ω is influenced by the solvent beyond the first coordination sphere. For determining ionization energies, a considerable number of solvent molecules on the first solvation shell must be taken into account. We demonstrate that accurately calculating optical gaps of solvated systems using OT-RSH can be done in three steps: (i) including the chemical environment when determining the range-separation parameter, (ii) taking into account the screening due to the solvent, and (iii) using realistic molecular geometries.
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Affiliation(s)
| | - Stephan Kümmel
- Theoretical Physics IV, University of Bayreuth, D-95440 Bayreuth, Germany
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47
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Bokareva OS, Grell G, Bokarev SI, Kühn O. Tuning Range-Separated Density Functional Theory for Photocatalytic Water Splitting Systems. J Chem Theory Comput 2015; 11:1700-9. [DOI: 10.1021/acs.jctc.5b00068] [Citation(s) in RCA: 51] [Impact Index Per Article: 5.7] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/09/2023]
Affiliation(s)
- Olga S. Bokareva
- Institut für Physik, Universität Rostock, Universitätsplatz 3, D-18055 Rostock, Germany
| | - Gilbert Grell
- Institut für Physik, Universität Rostock, Universitätsplatz 3, D-18055 Rostock, Germany
| | - Sergey I. Bokarev
- Institut für Physik, Universität Rostock, Universitätsplatz 3, D-18055 Rostock, Germany
| | - Oliver Kühn
- Institut für Physik, Universität Rostock, Universitätsplatz 3, D-18055 Rostock, Germany
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