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Zhou B, Zhou Y, Xie D. Accelerated Quantum Mechanics/Molecular Mechanics Simulations via Neural Networks Incorporated with Mechanical Embedding Scheme. J Chem Theory Comput 2023; 19:1157-1169. [PMID: 36724190 DOI: 10.1021/acs.jctc.2c01131] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 02/02/2023]
Abstract
A powerful tool to study the mechanism of reactions in solutions or enzymes is to perform the ab initio quantum mechanical/molecular mechanical (QM/MM) molecular dynamics (MD) simulations. However, the computational cost is too high due to the explicit electronic structure calculations at every time step of the simulation. A neural network (NN) method can accelerate the QM/MM-MD simulations, but it has long been a problem to accurately describe the QM/MM electrostatic coupling by NN in the electrostatic embedding (EE) scheme. In this work, we developed a new method to accelerate QM/MM calculations in the mechanic embedding (ME) scheme. The potentials and partial point charges of QM atoms are first learned in vacuo by the embedded atom neural networks (EANN) approach. MD simulations are then performed on this EANN/MM potential energy surface (PES) to obtain free energy (FE) profiles for reactions, in which the QM/MM electrostatic coupling is treated in the mechanic embedding (ME) scheme. Finally, a weighted thermodynamic perturbation (wTP) corrects the FE profiles in the ME scheme to the EE scheme. For two reactions in water and one in methanol, our simulations reproduced the B3LYP/MM free energy profiles within 0.5 kcal/mol with a speed-up of 30-60-fold. The results show that the strategy of combining EANN potential in the ME scheme with the wTP correction is efficient and reliable for chemical reaction simulations in liquid. Another advantage of our method is that the QM PES is independent of the MM subsystem, so it can be applied to various MM environments as demonstrated by an SN2 reaction studied in water and methanol individually, which used the same EANN PES. The free energy profiles are in excellent accordance with the results obtained from B3LYP/MM-MD simulations. In future, this method will be applied to the reactions of enzymes and their variants.
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Affiliation(s)
- Boyi Zhou
- Institute of Theoretical and Computational Chemistry, Key Laboratory of Mesoscopic Chemistry, School of Chemistry and Chemical Engineering, Nanjing University, Nanjing 210023, China
| | - Yanzi Zhou
- Institute of Theoretical and Computational Chemistry, Key Laboratory of Mesoscopic Chemistry, School of Chemistry and Chemical Engineering, Nanjing University, Nanjing 210023, China
| | - Daiqian Xie
- Institute of Theoretical and Computational Chemistry, Key Laboratory of Mesoscopic Chemistry, School of Chemistry and Chemical Engineering, Nanjing University, Nanjing 210023, China.,Hefei National Laboratory, Hefei 230088, China
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2
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Jeanmairet G, Levesque M, Borgis D. Tackling Solvent Effects by Coupling Electronic and Molecular Density Functional Theory. J Chem Theory Comput 2020; 16:7123-7134. [PMID: 32894674 DOI: 10.1021/acs.jctc.0c00729] [Citation(s) in RCA: 16] [Impact Index Per Article: 4.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/16/2022]
Abstract
Solvation effects can have a tremendous influence on chemical reactions. However, precise quantum chemistry calculations are most often done either in vacuum neglecting the role of the solvent or using continuum solvent model ignoring its molecular nature. We propose a new method coupling a quantum description of the solute using electronic density functional theory with a classical grand-canonical treatment of the solvent using molecular density functional theory. Unlike a previous work, both densities are minimized self-consistently, accounting for mutual polarization of the molecular solvent and the solute. The electrostatic interaction is accounted using the full electron density of the solute rather than fitted point charges. The introduced methodology represents a good compromise between the two main strategies to tackle solvation effects in quantum calculation. It is computationally more effective than a direct quantum mechanics/molecular mechanics coupling, requiring the exploration of many solvent configurations. Compared to continuum methods, it retains the full molecular-level description of the solvent. We validate this new framework onto two usual benchmark systems: a water solvated in water and the symmetrical nucleophilic substitution between chloromethane and chloride in water. The prediction for the free energy profiles are not yet fully quantitative compared to experimental data, but the most important features are qualitatively recovered. The method provides a detailed molecular picture of the evolution of the solvent structure along the reaction pathway.
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Affiliation(s)
- Guillaume Jeanmairet
- Sorbonne Université, CNRS, Physico-Chimie des Électrolytes et Nanosystèmes, Interfaciaux, PHENIX, F-75005 Paris, France.,Réseau sur le Stockage Électrochimique de l'Énergie (RS2E), FR CNRS 3459, 80039 Amiens Cedex, France
| | - Maximilien Levesque
- PASTEUR, Département de chimie, École normale supérieure, PSL University, Sorbonne, Université, CNRS, 75005 Paris, France.,Aqemia, 75006 Paris, France
| | - Daniel Borgis
- PASTEUR, Département de chimie, École normale supérieure, PSL University, Sorbonne, Université, CNRS, 75005 Paris, France.,Maison de la Simulation, CEA, CNRS, Université Paris-Sud, UVSQ, Université Paris-Saclay, 91191 Gif-sur-Yvette, France
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3
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Cai C, Tang W, Qiao C, Jiang P, Lu C, Zhao S, Liu H. A reaction density functional theory study of the solvent effect in prototype SN2 reactions in aqueous solution. Phys Chem Chem Phys 2019; 21:24876-24883. [DOI: 10.1039/c9cp03888d] [Citation(s) in RCA: 10] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/22/2023]
Abstract
Reaction density functional theory (RxDFT), combining quantum DFT with classical DFT, has been employed to investigate the solvent effect and free energy profiles of SN2 reactions in aqueous solution.
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Affiliation(s)
- Cheng Cai
- State Key Laboratory of Chemical Engineering and School of Chemical Engineering, East China University of Science and Technology
- Shanghai
- China
- School of Chemistry and Molecular Engineering
- East China University of Science and Technology
| | - Weiqiang Tang
- State Key Laboratory of Chemical Engineering and School of Chemical Engineering, East China University of Science and Technology
- Shanghai
- China
| | - Chongzhi Qiao
- State Key Laboratory of Chemical Engineering and School of Chemical Engineering, East China University of Science and Technology
- Shanghai
- China
| | - Peng Jiang
- State Key Laboratory of Chemical Engineering and School of Chemical Engineering, East China University of Science and Technology
- Shanghai
- China
| | - Changjie Lu
- State Key Laboratory of Chemical Engineering and School of Chemical Engineering, East China University of Science and Technology
- Shanghai
- China
| | - Shuangliang Zhao
- State Key Laboratory of Chemical Engineering and School of Chemical Engineering, East China University of Science and Technology
- Shanghai
- China
| | - Honglai Liu
- School of Chemistry and Molecular Engineering
- East China University of Science and Technology
- Shanghai
- China
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4
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Li P, Jia X, Pan X, Shao Y, Mei Y. Accelerated Computation of Free Energy Profile at ab Initio Quantum Mechanical/Molecular Mechanics Accuracy via a Semi-Empirical Reference Potential. I. Weighted Thermodynamics Perturbation. J Chem Theory Comput 2018; 14:5583-5596. [DOI: 10.1021/acs.jctc.8b00571] [Citation(s) in RCA: 34] [Impact Index Per Article: 5.7] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 02/01/2023]
Affiliation(s)
- Pengfei Li
- State Key Laboratory of Precision Spectroscopy, School of Physics and Materials Science, East China Normal University, Shanghai 200062, China
| | - Xiangyu Jia
- State Key Laboratory of Precision Spectroscopy, School of Physics and Materials Science, East China Normal University, Shanghai 200062, China
| | - Xiaoliang Pan
- Department of Chemistry and Biochemistry, University of Oklahoma, Norman, Oklahoma 73019, United States
| | - Yihan Shao
- Department of Chemistry and Biochemistry, University of Oklahoma, Norman, Oklahoma 73019, United States
| | - Ye Mei
- State Key Laboratory of Precision Spectroscopy, School of Physics and Materials Science, East China Normal University, Shanghai 200062, China
- Department of Chemistry and Biochemistry, University of Oklahoma, Norman, Oklahoma 73019, United States
- NYU-ECNU Center for Computational Chemistry at NYU Shanghai, Shanghai 200062, China
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5
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Satpathy L, Sahu PK, Behera PK, Mishra BK. Solvent Effect on the Potential Energy Surfaces of the F - + CH 3CH 2Br Reaction. J Phys Chem A 2018; 122:5861-5869. [PMID: 29909618 DOI: 10.1021/acs.jpca.8b02687] [Citation(s) in RCA: 11] [Impact Index Per Article: 1.8] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/30/2022]
Abstract
Although substantial work has been undertaken on reaction pathways involved in base-promoted elimination reactions and bimolecular nucleophilic substitution reaction of F- on CH3CH2X (X = Cl, Br, I), the effect of solvents with varying dielectric constants on the stereochemistry of each of the reaction species involved across the reaction profile have not yet been clearly understood. The present investigation reports the effect of solvents on the potential energy surfaces (PES) and structures of the species appearing in the reaction pathway of F- with bromoethane. The PESs in the gas phase have been computed at MP2 level and CCSD(T) level. The performance of several hybrid density functional, such as B3LYP, M06, M06L, BHandH, X3LYP, M05, M05-2X, and M06-2X have also been investigated toward describing the elimination and nucleophilic substitution reactions. With respect to MAE values and to make the computation cost-effective, we have explored the implicit continuum solvent model, CPCM in solvents like cyclohexane, methanol, acetonitrile, dimethyl sulfoxide and water. The reactant complexes proceed through the subsequent steps to produce fluoroethane as the substitution product and ethylene as one of the elimination products. For elimination reaction both syn and anti elimination have been explored. The calculated relatives energies values, which are negative in the gas phase, are found to be positive in polar solvents since the point charge in the separated reactants are more stabilized than the dispersed charge in the transient complex, which has also been analyzed through NBO analysis.
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Affiliation(s)
- Lopamudra Satpathy
- Centre of Studies in Surface Science and Technology, School of Chemistry , Sambalpur University , Jyoti Vihar 768 019 , India
| | - Prabhat K Sahu
- Computational Modeling Research Laboratory , School of Chemistry Sambalpur University , Jyoti Vihar 768 019 , India
| | - Pradipta K Behera
- Centre of Studies in Surface Science and Technology, School of Chemistry , Sambalpur University , Jyoti Vihar 768 019 , India
| | - Bijay K Mishra
- Centre of Studies in Surface Science and Technology, School of Chemistry , Sambalpur University , Jyoti Vihar 768 019 , India
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Hamlin TA, van Beek B, Wolters LP, Bickelhaupt FM. Nucleophilic Substitution in Solution: Activation Strain Analysis of Weak and Strong Solvent Effects. Chemistry 2018; 24:5927-5938. [PMID: 29457865 PMCID: PMC5947303 DOI: 10.1002/chem.201706075] [Citation(s) in RCA: 42] [Impact Index Per Article: 7.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/21/2017] [Indexed: 12/23/2022]
Abstract
We have quantum chemically studied the effect of various polar and apolar solvents on the shape of the potential energy surface (PES) of a diverse collection of archetypal nucleophilic substitution reactions at carbon, silicon, phosphorus, and arsenic by using density functional theory at the OLYP/TZ2P level. In the gas phase, all our model SN 2 reactions have single-well PESs, except for the nucleophilic substitution reaction at carbon (SN 2@C), which has a double-well energy profile. The presence of the solvent can have a significant effect on the shape of the PES and, thus, on the nature of the SN 2 process. Solvation energies, charges on the nucleophile or leaving group, and structural features are compared for the various SN 2 reactions in a spectrum of solvents. We demonstrate how solvation can change the shape of the PES, depending not only on the polarity of the solvent, but also on how the charge is distributed over the interacting molecular moieties during different stages of the reaction. In the case of a nucleophilic substitution at three-coordinate phosphorus, the reaction can be made to proceed through a single-well [no transition state (TS)], bimodal barrier (two TSs), and then through a unimodal transition state (one TS) simply by increasing the polarity of the solvent.
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Affiliation(s)
- Trevor A. Hamlin
- Department of Theoretical ChemistryAmsterdam Center for Multiscale Modeling (ACMM)Vrije Universiteit AmsterdamDe Boelelaan 10831081 HVAmsterdamThe Netherlands
| | - Bas van Beek
- Department of Theoretical ChemistryAmsterdam Center for Multiscale Modeling (ACMM)Vrije Universiteit AmsterdamDe Boelelaan 10831081 HVAmsterdamThe Netherlands
| | - Lando P. Wolters
- Department of Theoretical ChemistryAmsterdam Center for Multiscale Modeling (ACMM)Vrije Universiteit AmsterdamDe Boelelaan 10831081 HVAmsterdamThe Netherlands
| | - F. Matthias Bickelhaupt
- Department of Theoretical ChemistryAmsterdam Center for Multiscale Modeling (ACMM)Vrije Universiteit AmsterdamDe Boelelaan 10831081 HVAmsterdamThe Netherlands
- Institute of Molecules and Materials (IMM)Radboud University NijmegenHeyendaalseweg 1356525 AJNijmegenThe Netherlands
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7
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Ojeda-May P, Nam K. Acceleration of Semiempirical QM/MM Methods through Message Passage Interface (MPI), Hybrid MPI/Open Multiprocessing, and Self-Consistent Field Accelerator Implementations. J Chem Theory Comput 2017. [PMID: 28628742 DOI: 10.1021/acs.jctc.7b00322] [Citation(s) in RCA: 10] [Impact Index Per Article: 1.4] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/30/2022]
Abstract
The strategy and implementation of scalable and efficient semiempirical (SE) QM/MM methods in CHARMM are described. The serial version of the code was first profiled to identify routines that required parallelization. Afterward, the code was parallelized and accelerated with three approaches. The first approach was the parallelization of the entire QM/MM routines, including the Fock matrix diagonalization routines, using the CHARMM message passage interface (MPI) machinery. In the second approach, two different self-consistent field (SCF) energy convergence accelerators were implemented using density and Fock matrices as targets for their extrapolations in the SCF procedure. In the third approach, the entire QM/MM and MM energy routines were accelerated by implementing the hybrid MPI/open multiprocessing (OpenMP) model in which both the task- and loop-level parallelization strategies were adopted to balance loads between different OpenMP threads. The present implementation was tested on two solvated enzyme systems (including <100 QM atoms) and an SN2 symmetric reaction in water. The MPI version exceeded existing SE QM methods in CHARMM, which include the SCC-DFTB and SQUANTUM methods, by at least 4-fold. The use of SCF convergence accelerators further accelerated the code by ∼12-35% depending on the size of the QM region and the number of CPU cores used. Although the MPI version displayed good scalability, the performance was diminished for large numbers of MPI processes due to the overhead associated with MPI communications between nodes. This issue was partially overcome by the hybrid MPI/OpenMP approach which displayed a better scalability for a larger number of CPU cores (up to 64 CPUs in the tested systems).
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Affiliation(s)
| | - Kwangho Nam
- Department of Chemistry and Biochemistry, University of Texas at Arlington , Arlington, Texas 76019-0065, United States
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8
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Pedraza-González L, Galindo JF, González R, Reyes A. Revisiting the Dielectric Constant Effect on the Nucleophile and Leaving Group of Prototypical Backside S N2 Reactions: A Reaction Force and Atomic Contribution Analysis. J Phys Chem A 2016; 120:8360-8368. [PMID: 27718576 DOI: 10.1021/acs.jpca.6b06517] [Citation(s) in RCA: 9] [Impact Index Per Article: 1.1] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/28/2022]
Abstract
The solvent effect on the nucleophile and leaving group atoms of the prototypical F- + CH3Cl → CH3F + Cl- backside bimolecular nucleophilic substitution reaction (SN2) is analyzed employing the reaction force and the atomic contributions methods on the intrinsic reaction coordinate (IRC). Solvent effects were accounted for using the polarizable continuum solvent model. Calculations were performed employing 11 dielectric constants, ε, ranging from 1.0 to 78.5, to cover a wide spectrum of solvents. The reaction force data reveal that the solvent mainly influences the region of the IRC preceding the energy barrier, where the structural rearrangement to reach the transition state occurs. A detailed analysis of the atomic role in the reaction as a function of ε reveals that the nucleophile and the carbon atom are the ones that contribute the most to the energy barrier. In addition, we investigated the effect of the choice of nucleophile and leaving group on the ΔE0 and ΔE‡ of Y- + CH3X → YCH3 + X- (X, Y = F, Cl, Br, I) in aqueous solution. Our analysis allowed us to find relationships between the atomic contributions to the activation energy and leaving group ability and nucleophilicity.
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Affiliation(s)
- Laura Pedraza-González
- Departamento de Quı́mica, Universidad Nacional de Colombia , Av. Cra 30 # 45-03, Bogotá, Colombia
| | - Johan F Galindo
- Departamento de Quı́mica, Universidad Nacional de Colombia , Av. Cra 30 # 45-03, Bogotá, Colombia
| | - Ronald González
- Departamento de Quı́mica, Universidad Nacional de Colombia , Av. Cra 30 # 45-03, Bogotá, Colombia
| | - Andrés Reyes
- Departamento de Quı́mica, Universidad Nacional de Colombia , Av. Cra 30 # 45-03, Bogotá, Colombia
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9
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Kuechler ER, Giese TJ, York DM. Charge-dependent many-body exchange and dispersion interactions in combined QM/MM simulations. J Chem Phys 2016; 143:234111. [PMID: 26696050 DOI: 10.1063/1.4937166] [Citation(s) in RCA: 17] [Impact Index Per Article: 2.1] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/14/2022] Open
Abstract
Accurate modeling of the molecular environment is critical in condensed phase simulations of chemical reactions. Conventional quantum mechanical/molecular mechanical (QM/MM) simulations traditionally model non-electrostatic non-bonded interactions through an empirical Lennard-Jones (LJ) potential which, in violation of intuitive chemical principles, is bereft of any explicit coupling to an atom's local electronic structure. This oversight results in a model whereby short-ranged exchange-repulsion and long-ranged dispersion interactions are invariant to changes in the local atomic charge, leading to accuracy limitations for chemical reactions where significant atomic charge transfer can occur along the reaction coordinate. The present work presents a variational, charge-dependent exchange-repulsion and dispersion model, referred to as the charge-dependent exchange and dispersion (QXD) model, for hybrid QM/MM simulations. Analytic expressions for the energy and gradients are provided, as well as a description of the integration of the model into existing QM/MM frameworks, allowing QXD to replace traditional LJ interactions in simulations of reactive condensed phase systems. After initial validation against QM data, the method is demonstrated by capturing the solvation free energies of a series of small, chlorine-containing compounds that have varying charge on the chlorine atom. The model is further tested on the SN2 attack of a chloride anion on methylchloride. Results suggest that the QXD model, unlike the traditional LJ model, is able to simultaneously obtain accurate solvation free energies for a range of compounds while at the same time closely reproducing the experimental reaction free energy barrier. The QXD interaction model allows explicit coupling of atomic charge with many-body exchange and dispersion interactions that are related to atomic size and provides a more accurate and robust representation of non-electrostatic non-bonded QM/MM interactions.
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Affiliation(s)
- Erich R Kuechler
- BioMaPS Institute and Department of Chemistry and Chemical Biology, Rutgers University, Piscataway, New Jersey 08854-8087, USA
| | - Timothy J Giese
- BioMaPS Institute and Department of Chemistry and Chemical Biology, Rutgers University, Piscataway, New Jersey 08854-8087, USA
| | - Darrin M York
- BioMaPS Institute and Department of Chemistry and Chemical Biology, Rutgers University, Piscataway, New Jersey 08854-8087, USA
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10
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Vasilevskaya T, Thiel W. Periodic Boundary Conditions in QM/MM Calculations: Implementation and Tests. J Chem Theory Comput 2016; 12:3561-70. [DOI: 10.1021/acs.jctc.6b00269] [Citation(s) in RCA: 23] [Impact Index Per Article: 2.9] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/29/2022]
Affiliation(s)
| | - Walter Thiel
- Max-Planck-Institut
für Kohlenforschung, 45470 Mülheim an der Ruhr, Germany
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11
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Kuechler ER, Giese TJ, York DM. VR-SCOSMO: A smooth conductor-like screening model with charge-dependent radii for modeling chemical reactions. J Chem Phys 2016; 144:164115. [PMID: 27131539 PMCID: PMC4851621 DOI: 10.1063/1.4946779] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/18/2015] [Accepted: 04/01/2016] [Indexed: 12/23/2022] Open
Abstract
To better represent the solvation effects observed along reaction pathways, and of ionic species in general, a charge-dependent variable-radii smooth conductor-like screening model (VR-SCOSMO) is developed. This model is implemented and parameterized with a third order density-functional tight binding quantum model, DFTB3/3OB-OPhyd, a quantum method which was developed for organic and biological compounds, utilizing a specific parameterization for phosphate hydrolysis reactions. Unlike most other applications with the DFTB3/3OB model, an auxiliary set of atomic multipoles is constructed from the underlying DFTB3 density matrix which is used to interact the solute with the solvent response surface. The resulting method is variational, produces smooth energies, and has analytic gradients. As a baseline, a conventional SCOSMO model with fixed radii is also parameterized. The SCOSMO and VR-SCOSMO models shown have comparable accuracy in reproducing neutral-molecule absolute solvation free energies; however, the VR-SCOSMO model is shown to reduce the mean unsigned errors (MUEs) of ionic compounds by half (about 2-3 kcal/mol). The VR-SCOSMO model presents similar accuracy as a charge-dependent Poisson-Boltzmann model introduced by Hou et al. [J. Chem. Theory Comput. 6, 2303 (2010)]. VR-SCOSMO is then used to examine the hydrolysis of trimethylphosphate and seven other phosphoryl transesterification reactions with different leaving groups. Two-dimensional energy landscapes are constructed for these reactions and calculated barriers are compared to those obtained from ab initio polarizable continuum calculations and experiment. Results of the VR-SCOSMO model are in good agreement in both cases, capturing the rate-limiting reaction barrier and the nature of the transition state.
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Affiliation(s)
- Erich R Kuechler
- Department of Chemistry and Chemical Biology, Rutgers University, Piscataway, New Jersey 08854-8087, USA
| | - Timothy J Giese
- Department of Chemistry and Chemical Biology, Rutgers University, Piscataway, New Jersey 08854-8087, USA
| | - Darrin M York
- Department of Chemistry and Chemical Biology, Rutgers University, Piscataway, New Jersey 08854-8087, USA
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Saez DA, Vogt-Geisse S, Inostroza-Rivera R, Kubař T, Elstner M, Toro-Labbé A, Vöhringer-Martinez E. The effect of the environment on the methyl transfer reaction mechanism between trimethylsulfonium and phenolate. Phys Chem Chem Phys 2016; 18:24033-42. [DOI: 10.1039/c6cp02821g] [Citation(s) in RCA: 6] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 02/02/2023]
Abstract
The methyl transfer reaction mechanism in different molecular environments were studied by electronic structure methods and QM/MM molecular dynamics simulations.
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Affiliation(s)
- David Adrian Saez
- Departamento de Físico-Química
- Facultad de Ciencias Químicas
- Universidad de Concepción
- Millenium Nucleus Chemical Processes and Catalysis (CPC)
- Chile
| | - Stefan Vogt-Geisse
- Departamento de Físico-Química
- Facultad de Ciencias Químicas
- Universidad de Concepción
- Millenium Nucleus Chemical Processes and Catalysis (CPC)
- Chile
| | | | - Tomáš Kubař
- Center for Functional Nanomaterials
- Karlsruhe Institute of Technology
- Germany
- Institute for Physical Chemistry
- Karlsruhe Institute of Technology
| | - Marcus Elstner
- Institute for Physical Chemistry
- Karlsruhe Institute of Technology
- 76131 Karlsruhe
- Germany
| | - Alejandro Toro-Labbé
- QTC
- Facultad de Química
- Pontificia Universidad Católica de Chile
- Millenium Nucleus Chemical Processes and Catalysis (CPC)
- Chile
| | - Esteban Vöhringer-Martinez
- Departamento de Físico-Química
- Facultad de Ciencias Químicas
- Universidad de Concepción
- Millenium Nucleus Chemical Processes and Catalysis (CPC)
- Chile
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Welborn M, Chen J, Wang LP, Van Voorhis T. Why many semiempirical molecular orbital theories fail for liquid water and how to fix them. J Comput Chem 2015; 36:934-9. [PMID: 25766721 DOI: 10.1002/jcc.23887] [Citation(s) in RCA: 11] [Impact Index Per Article: 1.2] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/28/2014] [Revised: 12/16/2014] [Accepted: 02/08/2015] [Indexed: 11/06/2022]
Abstract
Water is an extremely important liquid for chemistry and the search for more accurate force fields for liquid water continues unabated. Neglect of diatomic differential overlap (NDDO) molecular orbital methods provide and intriguing generalization of classical force fields in this regard because they can account both for bond breaking and electronic polarization of molecules. However, we show that most standard NDDO methods fail for water because they give an incorrect description of hydrogen bonding, water's key structural feature. Using force matching, we design a reparameterized NDDO model and find that it qualitatively reproduces the experimental radial distribution function of water, as well as various monomer, dimer, and bulk properties that PM6 does not. This suggests that the apparent limitations of NDDO models are primarily due to poor parameterization and not to the NDDO approximations themselves. Finally, we identify the physical parameters that most influence the condensed phase properties. These results help to elucidate the chemistry that a semiempirical molecular orbital picture of water must capture. We conclude that properly parameterized NDDO models could be useful for simulations that require electronically detailed explicit solvent, including the calculation of redox potentials and simulation of charge transfer and photochemistry.
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Affiliation(s)
- Matthew Welborn
- Department of Chemistry, Massachusetts Institute of Technology, 77 Massachusetts Avenue, Cambridge, Massachusetts, 02139
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