1
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Fedorov DG. Analysis of Site Energies and Excitonic Couplings: The Role of Symmetry and Polarization. J Phys Chem A 2024; 128:1154-1162. [PMID: 38302431 DOI: 10.1021/acs.jpca.3c06293] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 02/03/2024]
Abstract
An excitonic coupling model is developed based on an equation-of-motion coupled cluster combined with the fragment molecular orbital method. The effects of polarization and excitonic coupling on the splitting of quasi-degenerate levels in systems containing multiple chromophores are elucidated on dimers of formaldehyde, water, formic acid, hydrogen fluoride, and carbon monoxide. It is shown that the level structure is mainly determined by the mutual polarization of chromophores and to a lesser extent by the excitonic coupling. The role of symmetry in excitonic coupling in dimers is discussed. The excitonic coupling between all residues in the photoactive yellow protein (PDB: 2PHY) is analyzed.
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Affiliation(s)
- Dmitri G Fedorov
- Research Center for Computational Design of Advanced Functional Materials (CD-FMat), National Institute of Advanced Industrial Science and Technology (AIST), Central 2, Umezono 1-1-1, Tsukuba 305-8568, Japan
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2
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Heindel JP, Herman KM, Xantheas SS. Many-Body Effects in Aqueous Systems: Synergies Between Interaction Analysis Techniques and Force Field Development. Annu Rev Phys Chem 2023; 74:337-360. [PMID: 37093659 DOI: 10.1146/annurev-physchem-062422-023532] [Citation(s) in RCA: 3] [Impact Index Per Article: 3.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 04/25/2023]
Abstract
Interaction analysis techniques, including the many-body expansion (MBE), symmetry-adapted perturbation theory, and energy decomposition analysis, allow for an intuitive understanding of complex molecular interactions. We review these methods by first providing a historical context for the study of many-body interactions and discussing how nonadditivities emerge from Hamiltonians containing strictly pairwise-additive interactions. We then elaborate on the synergy between these interaction analysis techniques and the development of advanced force fields aimed at accurately reproducing the Born-Oppenheimer potential energy surface. In particular, we focus on ab initio-based force fields that aim to explicitly reproduce many-body terms and are fitted to high-level electronic structure results. These force fields generally incorporate many-body effects through (a) parameterization of distributed multipoles, (b) explicit fitting of the MBE, (c) inclusion of many-atom features in a neural network, and (d) coarse-graining of many-body terms into an effective two-body term. We also discuss the emerging use of the MBE to improve the accuracy and speed of ab initio molecular dynamics.
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Affiliation(s)
- Joseph P Heindel
- Department of Chemistry, University of Washington, Seattle, Washington, USA
| | - Kristina M Herman
- Department of Chemistry, University of Washington, Seattle, Washington, USA
| | - Sotiris S Xantheas
- Department of Chemistry, University of Washington, Seattle, Washington, USA
- Advanced Computing, Mathematics and Data Division, Pacific Northwest National Laboratory, Richland, Washington, USA; ,
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3
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Altun A, Neese F, Bistoni G. Open-Shell Variant of the London Dispersion-Corrected Hartree-Fock Method (HFLD) for the Quantification and Analysis of Noncovalent Interaction Energies. J Chem Theory Comput 2022; 18:2292-2307. [PMID: 35167304 PMCID: PMC9009084 DOI: 10.1021/acs.jctc.1c01295] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/29/2022]
Abstract
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The London dispersion
(LD)-corrected Hartree–Fock (HF) method
(HFLD) is an ab initio approach for the quantification
and analysis of noncovalent interactions (NCIs) in large systems that
is based on the domain-based local pair natural orbital coupled-cluster
(DLPNO-CC) theory. In the original HFLD paper, we discussed the implementation,
accuracy, and efficiency of its closed-shell variant. Herein, an extension
of this method to open-shell molecular systems is presented. Its accuracy
is tested on challenging benchmark sets for NCIs, using CCSD(T) energies
at the estimated complete basis set limit as reference. The HFLD scheme
was found to be as accurate as the best-performing dispersion-corrected
exchange-correlation functionals, while being nonempirical and equally
efficient. In addition, it can be combined with the well-established
local energy decomposition (LED) for the analysis of NCIs, thus yielding
additional physical insights.
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Affiliation(s)
- Ahmet Altun
- Max-Planck-Institut für Kohlenforschung, Kaiser-Wilhelm-Platz 1, D-45470 Mülheim an der Ruhr, Germany
| | - Frank Neese
- Max-Planck-Institut für Kohlenforschung, Kaiser-Wilhelm-Platz 1, D-45470 Mülheim an der Ruhr, Germany
| | - Giovanni Bistoni
- Max-Planck-Institut für Kohlenforschung, Kaiser-Wilhelm-Platz 1, D-45470 Mülheim an der Ruhr, Germany.,Department of Chemistry, Biology and Biotechnology, University of Perugia, 06123 Perugia, Italy
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4
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Altun A, Ghosh S, Riplinger C, Neese F, Bistoni G. Addressing the System-Size Dependence of the Local Approximation Error in Coupled-Cluster Calculations. J Phys Chem A 2021; 125:9932-9939. [PMID: 34730360 PMCID: PMC8607505 DOI: 10.1021/acs.jpca.1c09106] [Citation(s) in RCA: 15] [Impact Index Per Article: 5.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/30/2022]
Abstract
Over the last two decades, the local approximation has been successfully used to extend the range of applicability of the "gold standard" singles and doubles coupled-cluster method with perturbative triples CCSD(T) to systems with hundreds of atoms. The local approximation error grows in absolute value with the increasing system size, i.e., by increasing the number of electron pairs in the system. In this study, we demonstrate that the recently introduced two-point extrapolation scheme for approaching the complete pair natural orbital (PNOs) space limit in domain-based pair natural orbital CCSD(T) calculations drastically reduces the dependence of the error on the system size, thus opening up unprecedented opportunities for the calculation of benchmark quality relative energies for large systems.
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Affiliation(s)
- Ahmet Altun
- Max-Planck-Institut für Kohlenforschung, Kaiser-Wilhelm-Platz 1, D-45470 Mülheim an der Ruhr, Germany
| | - Soumen Ghosh
- Max-Planck-Institut für Kohlenforschung, Kaiser-Wilhelm-Platz 1, D-45470 Mülheim an der Ruhr, Germany
| | | | - Frank Neese
- Max-Planck-Institut für Kohlenforschung, Kaiser-Wilhelm-Platz 1, D-45470 Mülheim an der Ruhr, Germany
| | - Giovanni Bistoni
- Max-Planck-Institut für Kohlenforschung, Kaiser-Wilhelm-Platz 1, D-45470 Mülheim an der Ruhr, Germany
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5
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Loipersberger M, Bertels LW, Lee J, Head-Gordon M. Exploring the Limits of Second- and Third-Order Møller-Plesset Perturbation Theories for Noncovalent Interactions: Revisiting MP2.5 and Assessing the Importance of Regularization and Reference Orbitals. J Chem Theory Comput 2021; 17:5582-5599. [PMID: 34382394 PMCID: PMC9948597 DOI: 10.1021/acs.jctc.1c00469] [Citation(s) in RCA: 5] [Impact Index Per Article: 1.7] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 02/04/2023]
Abstract
This work systematically assesses the influence of reference orbitals, regularization, and scaling on the performance of second- and third-order Møller-Plesset perturbation theory wave function methods for noncovalent interactions (NCIs). Testing on 19 data sets (A24, DS14, HB15, HSG, S22, X40, HW30, NC15, S66, AlkBind12, CO2Nitrogen16, HB49, Ionic43, TA13, XB18, Bauza30, CT20, XB51, and Orel26rad) covers a wide range of different NCIs including hydrogen bonding, dispersion, and halogen bonding. Inclusion of potential energy surfaces from different hydrogen bonds and dispersion-bound complexes gauges accuracy for nonequilibrium geometries. Fifteen methods are tested. In notation where nonstandard choices of orbitals are denoted as methods:orbitals, these are MP2, κ-MP2, SCS-MP2, OOMP2, κ-OOMP2, MP3, MP2.5, MP3:OOMP2, MP2.5:OOMP2, MP3:κ-OOMP2, MP2.5:κ-OOMP2, κ-MP3:κ-OOMP2, κ-MP2.5:κ-OOMP2, MP3:ωB97X-V, and MP2.5:ωB97X-V. Furthermore, we compare these methods to the ωB97M-V and B3LYP-D3 density functionals, as well as CCSD. We find that the κ-regularization (κ = 1.45 au was used throughout) improves the energetics in almost all data sets for both MP2 (in 17 out of 19 data sets) and OOMP2 (16 out of 19). The improvement is significant (e.g., the root-mean-square deviation (RMSD) for the S66 data set is 0.29 kcal/mol for κ-OOMP2 versus 0.67 kcal/mol for MP2) and for interactions between stable closed-shell molecules, not strongly dependent on the reference orbitals. Scaled MP3 (with a factor of 0.5) using κ-OOMP2 reference orbitals (MP2.5:κ-OOMP2) provides significantly more accurate results for NCIs across all data sets with noniterative O(N6) scaling (S66 data set RMSD: 0.10 kcal/mol). Across the entire data set of 356 points, the improvement over standard MP2.5 is approximately a factor of 2: RMSD for MP3:κ-OOMP2 is 0.25 vs 0.50 kcal/mol for MP2.5. The use of high-quality density functional reference orbitals (ωB97X-V) also significantly improves the results of MP2.5 for NCI over a Hartree-Fock orbital reference. All our assessments and conclusions are based on the use of the medium-sized aug-cc-pVTZ basis to yield results that are directly compared against complete basis set limit reference values.
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Affiliation(s)
| | - Luke W. Bertels
- Department of Chemistry, University of California, Berkeley, California 94720, USA,Present Address: Department of Chemistry, Virginia Tech, Blacksburg, VA 24061, USA
| | - Joonho Lee
- Department of Chemistry, University of California, Berkeley, California 94720, USA,Present Address: Department of Chemistry, Columbia University, NY
| | - Martin Head-Gordon
- Department of Chemistry, University of California, Berkeley, California 94720, USA,Chemical Sciences Division, Lawrence Berkeley National Laboratory, Berkeley, California 94720, USA
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6
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Mao Y, Loipersberger M, Horn PR, Das A, Demerdash O, Levine DS, Prasad Veccham S, Head-Gordon T, Head-Gordon M. From Intermolecular Interaction Energies and Observable Shifts to Component Contributions and Back Again: A Tale of Variational Energy Decomposition Analysis. Annu Rev Phys Chem 2021; 72:641-666. [PMID: 33636998 DOI: 10.1146/annurev-physchem-090419-115149] [Citation(s) in RCA: 41] [Impact Index Per Article: 13.7] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/09/2022]
Abstract
Quantum chemistry in the form of density functional theory (DFT) calculations is a powerful numerical experiment for predicting intermolecular interaction energies. However, no chemical insight is gained in this way beyond predictions of observables. Energy decomposition analysis (EDA) can quantitatively bridge this gap by providing values for the chemical drivers of the interactions, such as permanent electrostatics, Pauli repulsion, dispersion, and charge transfer. These energetic contributions are identified by performing DFT calculations with constraints that disable components of the interaction. This review describes the second-generation version of the absolutely localized molecular orbital EDA (ALMO-EDA-II). The effects of different physical contributions on changes in observables such as structure and vibrational frequencies upon complex formation are characterized via the adiabatic EDA. Example applications include red- versus blue-shifting hydrogen bonds; the bonding and frequency shifts of CO, N2, and BF bound to a [Ru(II)(NH3)5]2 + moiety; and the nature of the strongly bound complexes between pyridine and the benzene and naphthalene radical cations. Additionally, the use of ALMO-EDA-II to benchmark and guide the development of advanced force fields for molecular simulation is illustrated with the recent, very promising, MB-UCB potential.
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Affiliation(s)
- Yuezhi Mao
- Pitzer Theory Center and Department of Chemistry, University of California, Berkeley, California 94720, USA;
| | - Matthias Loipersberger
- Pitzer Theory Center and Department of Chemistry, University of California, Berkeley, California 94720, USA;
| | - Paul R Horn
- Pitzer Theory Center and Department of Chemistry, University of California, Berkeley, California 94720, USA;
| | - Akshaya Das
- Pitzer Theory Center and Department of Chemistry, University of California, Berkeley, California 94720, USA; .,Department of Bioengineering and Department of Chemical and Biomolecular Engineering, University of California, Berkeley, California 94720, USA
| | - Omar Demerdash
- Pitzer Theory Center and Department of Chemistry, University of California, Berkeley, California 94720, USA; .,Department of Bioengineering and Department of Chemical and Biomolecular Engineering, University of California, Berkeley, California 94720, USA
| | - Daniel S Levine
- Pitzer Theory Center and Department of Chemistry, University of California, Berkeley, California 94720, USA;
| | - Srimukh Prasad Veccham
- Pitzer Theory Center and Department of Chemistry, University of California, Berkeley, California 94720, USA;
| | - Teresa Head-Gordon
- Pitzer Theory Center and Department of Chemistry, University of California, Berkeley, California 94720, USA; .,Department of Bioengineering and Department of Chemical and Biomolecular Engineering, University of California, Berkeley, California 94720, USA
| | - Martin Head-Gordon
- Pitzer Theory Center and Department of Chemistry, University of California, Berkeley, California 94720, USA;
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7
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Veccham SP, Lee J, Mao Y, Horn PR, Head-Gordon M. A non-perturbative pairwise-additive analysis of charge transfer contributions to intermolecular interaction energies. Phys Chem Chem Phys 2021; 23:928-943. [DOI: 10.1039/d0cp05852a] [Citation(s) in RCA: 8] [Impact Index Per Article: 2.7] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/21/2022]
Abstract
A non-perturbative scheme for complete decomposition of energy and charge associated with charge transfer interaction into pairwise additive components.
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Affiliation(s)
| | - Joonho Lee
- Department of Chemistry
- University of California
- Berkeley
- USA
- Chemical Sciences Division
| | - Yuezhi Mao
- Department of Chemistry
- University of California
- Berkeley
- USA
- Chemical Sciences Division
| | - Paul R. Horn
- Department of Chemistry
- University of California
- Berkeley
- USA
- Chemical Sciences Division
| | - Martin Head-Gordon
- Department of Chemistry
- University of California
- Berkeley
- USA
- Chemical Sciences Division
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8
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Grofe A, Zhao R, Wildman A, Stetina TF, Li X, Bao P, Gao J. Generalization of Block-Localized Wave Function for Constrained Optimization of Excited Determinants. J Chem Theory Comput 2020; 17:277-289. [PMID: 33356213 DOI: 10.1021/acs.jctc.0c01049] [Citation(s) in RCA: 12] [Impact Index Per Article: 3.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/30/2022]
Abstract
The block-localized wave function method is useful to provide insights on chemical bonding and intermolecular interactions through energy decomposition analysis. The method relies on block localization of molecular orbitals (MOs) by constraining the orbitals to basis functions within given blocks. Here, a generalized block-localized orbital (GBLO) method is described to allow both physically localized and delocalized MOs to be constrained in orbital-block definitions. Consequently, GBLO optimization can be conveniently tailored by imposing specific constraints. The GBLO method is illustrated by three examples: (1) constrained polarization response orbitals through dipole and quadrupole perturbation in a water dimer complex, (2) the ground and first excited-state potential energy curves of ethene about its C-C bond rotation, and (3) excitation energies of double electron excited states. Multistate density functional theory is used to determine the energies of the adiabatic ground and excited states using a minimal active space (MAS) comprising specifically charge-constrained and excited determinant configurations that are variationally optimized by the GBLO method. We find that the GBLO expansion that includes delocalized MOs in configurational blocks significantly reduces computational errors in comparison with physical block localization, and the computed ground- and excited-state energies are in good accordance with experiments and results obtained from multireference configuration interaction calculations.
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Affiliation(s)
- Adam Grofe
- Laboratory of Theoretical and Computational Chemistry, Institute of Theoretical Chemistry, Jilin University, Changchun, Jilin 130023, China.,Institute of Systems and Physical Biology, Shenzhen Bay Laboratory, Shenzhen 518055, China.,Department of Chemistry, University of Washington, Seattle, Washington 98195, United States
| | - Ruoqi Zhao
- Laboratory of Theoretical and Computational Chemistry, Institute of Theoretical Chemistry, Jilin University, Changchun, Jilin 130023, China.,Institute of Systems and Physical Biology, Shenzhen Bay Laboratory, Shenzhen 518055, China
| | - Andrew Wildman
- Department of Chemistry, University of Washington, Seattle, Washington 98195, United States
| | - Torin F Stetina
- Department of Chemistry, University of Washington, Seattle, Washington 98195, United States
| | - Xiaosong Li
- Department of Chemistry, University of Washington, Seattle, Washington 98195, United States
| | - Peng Bao
- Beijing National Laboratory for Molecular Sciences, State Key Laboratory for Structural Chemistry of Unstable and Stable Species, Institute of Chemistry, Chinese Academy of Sciences, Beijing 100190, China
| | - Jiali Gao
- Institute of Systems and Physical Biology, Shenzhen Bay Laboratory, Shenzhen 518055, China.,Department of Chemistry and Supercomputing Institute, University of Minnesota, Minneapolis, Minnesota 55455, United States.,Beijing University Shenzhen Graduate School, Shenzhen 518055, China
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9
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Zhang Z, Lu T, Ding L, Wang G, Wang Z, Zheng B, Liu Y, Ding XL. Cooperativity effects between regium-bonding and pnicogen-bonding interactions in ternary MF···PH3O···MF (M = Cu, Ag, Au): an ab initio study. Mol Phys 2020. [DOI: 10.1080/00268976.2020.1784478] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/24/2022]
Affiliation(s)
- Zan Zhang
- Key Laboratory of Theoretical Organic Chemistry and Functional Molecular, Ministry of Education, Hunan University of Science and Technology, Xiangtan, People’s Republic of China
- Laboratory of Controllable Preparation and Functional Application of Fine Polymers, School of Chemistry and Chemical Engineering, Hunan University of Science and Technology, Xiangtan, People’s Republic of China
| | - Tian Lu
- Beijing Kein Research Center for Natural Sciences, Beijing, People’s Republic of China
| | - Luyang Ding
- Key Laboratory of Theoretical Organic Chemistry and Functional Molecular, Ministry of Education, Hunan University of Science and Technology, Xiangtan, People’s Republic of China
- Laboratory of Controllable Preparation and Functional Application of Fine Polymers, School of Chemistry and Chemical Engineering, Hunan University of Science and Technology, Xiangtan, People’s Republic of China
| | - Guanyu Wang
- Key Laboratory of Theoretical Organic Chemistry and Functional Molecular, Ministry of Education, Hunan University of Science and Technology, Xiangtan, People’s Republic of China
- Laboratory of Controllable Preparation and Functional Application of Fine Polymers, School of Chemistry and Chemical Engineering, Hunan University of Science and Technology, Xiangtan, People’s Republic of China
| | - Zhaoxu Wang
- Key Laboratory of Theoretical Organic Chemistry and Functional Molecular, Ministry of Education, Hunan University of Science and Technology, Xiangtan, People’s Republic of China
- Laboratory of Controllable Preparation and Functional Application of Fine Polymers, School of Chemistry and Chemical Engineering, Hunan University of Science and Technology, Xiangtan, People’s Republic of China
| | - Baishu Zheng
- Key Laboratory of Theoretical Organic Chemistry and Functional Molecular, Ministry of Education, Hunan University of Science and Technology, Xiangtan, People’s Republic of China
- Laboratory of Controllable Preparation and Functional Application of Fine Polymers, School of Chemistry and Chemical Engineering, Hunan University of Science and Technology, Xiangtan, People’s Republic of China
| | - Yuan Liu
- Key Laboratory of Theoretical Organic Chemistry and Functional Molecular, Ministry of Education, Hunan University of Science and Technology, Xiangtan, People’s Republic of China
- Laboratory of Controllable Preparation and Functional Application of Fine Polymers, School of Chemistry and Chemical Engineering, Hunan University of Science and Technology, Xiangtan, People’s Republic of China
| | - Xun Lei Ding
- Institute of Clusters and Low Dimensional Nanomaterials, School of Mathematics and Physics, North China Electric Power University, Beijing, People’s Republic of China
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10
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Bandyopadhyay P, Seikh MM. Components of the interaction energy of the odd-electron halogen bond: an ab initio study. Phys Chem Chem Phys 2020; 22:15389-15400. [PMID: 32598430 DOI: 10.1039/d0cp02619k] [Citation(s) in RCA: 5] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/21/2022]
Abstract
In the realm of non-covalent interactions (NCI), the odd-electron halogen bond offers a fertile ground to explore the nature of such weak interactions. Here, an ab initio study of odd-electron halogen bonding (XB) is reported. The interactions of five radicals with several freons and interhalogens are studied using the Møller-Plesset (MP2) method. The regioselectivity, interaction energy and the components of the interaction energy of odd-electron XB were tuned by judicial selection of donor-acceptor pairs as revealed by scrutinizing the conceptual DFT parameters, NCI plot and LED-DLPNO-CCSD(T) analysis. The contribution from dispersion interaction is rather high for all XB bonded complexes and it increases when the interacting atom of the XB donor is highly polarizable. Additionally, the polarisation and intermolecular charge-transfer also contribute significantly when both the donor and acceptor atoms are soft species, resulting in a soft-soft interaction. We believe that our finding will not only shed new light on non-covalent interaction of odd-electron XB but will also be able to capture the pnictogen, chalcogen and tetrel bonding interactions. The ability of conceptual DFT parameters to predict the interaction energy and its components shown in this study will be helpful for tuning of substrates for desired products, modelling bio/macromolecules and crystal engineering.
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11
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Mao Y, Levine DS, Loipersberger M, Horn PR, Head-Gordon M. Probing radical-molecule interactions with a second generation energy decomposition analysis of DFT calculations using absolutely localized molecular orbitals. Phys Chem Chem Phys 2020; 22:12867-12885. [PMID: 32510096 DOI: 10.1039/d0cp01933j] [Citation(s) in RCA: 13] [Impact Index Per Article: 3.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/21/2022]
Abstract
Intermolecular interactions between radicals and closed-shell molecules are ubiquitous in chemical processes, ranging from the benchtop to the atmosphere and extraterrestrial space. While energy decomposition analysis (EDA) schemes for closed-shell molecules can be generalized for studying radical-molecule interactions, they face challenges arising from the unique characteristics of the electronic structure of open-shell species. In this work, we introduce additional steps that are necessary for the proper treatment of radical-molecule interactions to our previously developed unrestricted Absolutely Localized Molecular Orbital (uALMO)-EDA based on density functional theory calculations. A "polarize-then-depolarize" (PtD) scheme is used to remove arbitrariness in the definition of the frozen wavefunction, rendering the ALMO-EDA results independent of the orientation of the unpaired electron obtained from isolated fragment calculations. The contribution of radical rehybridization to polarization energies is evaluated. It is also valuable to monitor the wavefunction stability of each intermediate state, as well as their associated spin density profiles, to ensure the EDA results correspond to a desired electronic state. These radical extensions are incorporated into the "vertical" and "adiabatic" variants of uALMO-EDA for studies of energy changes and property shifts upon complexation. The EDA is validated on two model complexes, H2O˙F and FH˙OH. It is then applied to several chemically interesting radical-molecule complexes, including the sandwiched and T-shaped benzene dimer radical cation, complexes of pyridine with benzene and naphthalene radical cations, binary and ternary complexes of the hydroxyl radical with water (˙OH(H2O) and ˙OH(H2O)2), and the pre-reactive complexes and transition states in the ˙OH + HCHO and ˙OH + CH3CHO reactions. These examples suggest that this second generation uALMO-EDA is a useful tool for furthering one's understanding of both energetic and property changes associated with radical-molecule interactions.
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Affiliation(s)
- Yuezhi Mao
- Kenneth S. Pitzer Center for Theoretical Chemistry, Department of Chemistry, University of California at Berkeley, Berkeley, CA 94720, USA.
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