1
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Houston PL, Qu C, Yu Q, Pandey P, Conte R, Nandi A, Bowman JM. No Headache for PIPs: A PIP Potential for Aspirin Runs Much Faster and with Similar Precision Than Other Machine-Learned Potentials. J Chem Theory Comput 2024; 20:3008-3018. [PMID: 38593438 DOI: 10.1021/acs.jctc.4c00054] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 04/11/2024]
Abstract
Assessments of machine-learning (ML) potentials are an important aspect of the rapid development of this field. We recently reported an assessment of the linear-regression permutationally invariant polynomial (PIP) method for ethanol, using the widely used (revised) rMD17 data set. We demonstrated that the PIP approach outperformed numerous other methods, e.g., ANI, PhysNet, sGDML, and p-KRR, with respect to precision and notably with respect to speed [Houston et al., J. Chem. Phys. 2022, 156, 044120]. Here, we extend this assessment to the 21-atom aspirin molecule, using the rMD17 data set, with a focus on the speed of evaluation. Both energies and forces are used for training, and the precision of several PIPs is examined for both. Normal mode frequencies, the methyl torsional potential, and 1d vibrational energies for an OH stretch are presented. We show that the PIP approach achieves the level of precision obtained from other ML methods, e.g., atom-centered neural network methods, linear regression ACE, and kernel methods, as reported by Kovács et al. in J. Chem. Theory Comput. 2021, 17, 7696-7711. More significantly, we show that the PIP PESs run much faster than all other ML methods, whose timings were evaluated in that paper. We also show that the PIP PES extrapolates well enough to describe several internal motions of aspirin, including an OH stretch.
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Affiliation(s)
- Paul L Houston
- Department of Chemistry and Chemical Biology, Cornell University, Ithaca, New York 14853, United States
- Department of Chemistry and Biochemistry, Georgia Institute of Technology, Atlanta, Georgia 30332, United States
| | - Chen Qu
- Independent Researcher, Toronto, Ontario M9B0E3, Canada
| | - Qi Yu
- Department of Chemistry, Fudan University, Shanghai 200438, P. R. China
| | - Priyanka Pandey
- Department of Chemistry, Cherry L. Emerson Center for Scientific Computation, Emory University, Atlanta, Georgia 30322, United States
| | - Riccardo Conte
- Dipartimento di Chimica, Università degli Studi di Milano, via Golgi 19, 20133 Milano, Italy
| | - Apurba Nandi
- Department of Chemistry, Cherry L. Emerson Center for Scientific Computation, Emory University, Atlanta, Georgia 30322, United States
- Department of Physics and Materials Science, University of Luxembourg, Luxembourg City L-1511, Luxembourg
| | - Joel M Bowman
- Department of Chemistry, Cherry L. Emerson Center for Scientific Computation, Emory University, Atlanta, Georgia 30322, United States
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2
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Yu Y, Yang D, Zhou Y, Xie D. A New Full-Dimensional Ab Initio Intermolecular Potential Energy Surface and Rovibrational Energies of the H 2O-H 2 Complex. J Phys Chem A 2024; 128:170-181. [PMID: 38109882 DOI: 10.1021/acs.jpca.3c06805] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/20/2023]
Abstract
H2O-H2 is a prototypical five-atom van der Waals system, and the interaction between H2O and H2 plays an important role in many physical and chemical environments. However, previous full-dimensional intermolecular potential energy surfaces (IPESs) cannot accurately describe the H2O-H2 interaction in the repulsive or van der Waals minimum region. In this work, we constructed a full-dimensional IPES for the title system with a small root-mean-square error of 0.252 cm-1 by using the permutation invariant polynomial neural network method. The ab initio calculations were performed by employing the explicitly corrected coupled cluster [CCSD(T)-F12a] method with the augmented correlation-consistent polarized valence quintuple-ζ basis set. Based on the newly developed IPES, the bound states of the H2O-H2 complex were calculated within the rigid-rotor approximation. The transition frequencies and band origins agreed well with the experimental values [Weida, M. J.; Nesbitt, D. J. J. Chem. Phys. 1999, 110, 156-167] with errors less than 0.1 cm-1 for most transitions. Those results demonstrate the high accuracy of our new IPES, which would build a solid foundation for the collisional dynamics of H2O-H2 at low temperatures.
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Affiliation(s)
- Yipeng Yu
- Institute of Theoretical and Computational Chemistry, Key Laboratory of Mesoscopic Chemistry, School of Chemistry and Chemical Engineering, Nanjing University, Nanjing 210023, China
| | - Dongzheng Yang
- Department of Chemistry and Chemical Biology, University of New Mexico, Albuquerque, New Mexico 87131, United States
| | - 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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3
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Hellmann R. Cross Second Virial Coefficients of the H 2O-H 2 and H 2S-H 2 Systems from First-Principles. JOURNAL OF CHEMICAL AND ENGINEERING DATA 2023; 68:2212-2222. [PMID: 37736252 PMCID: PMC10510380 DOI: 10.1021/acs.jced.3c00300] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Grants] [Track Full Text] [Figures] [Subscribe] [Scholar Register] [Received: 05/23/2023] [Accepted: 07/14/2023] [Indexed: 09/23/2023]
Abstract
The cross second virial coefficients B12 for the interactions of water (H2O) with molecular hydrogen (H2) and of hydrogen sulfide (H2S) with H2 were obtained at temperatures in the range from 150 to 2000 K from new intermolecular potential energy surfaces (PESs) for the respective molecule pairs. The PESs are based on interaction energies determined for about 12 000 configurations of each molecule pair employing different high-level quantum-chemical ab initio methods up to coupled cluster with single, double, triple, and perturbative quadruple excitations [CCSDT(Q)]. Furthermore, the interaction energies were corrected for scalar relativistic effects. Both classical and semiclassical values for B12 were extracted from the PESs using the Mayer-sampling Monte Carlo approach. While our results for the H2O-H2 system validate the older first-principles results of Hodges et al. [J. Chem. Phys. 2004, 120, 710-720], B12 for the H2S-H2 system was, to the best of our knowledge, hitherto neither measured experimentally nor predicted from first principles.
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Affiliation(s)
- Robert Hellmann
- Institut für Thermodynamik, Helmut-Schmidt-Universität/Universität
der Bundeswehr Hamburg, Holstenhofweg 85, 22043 Hamburg, Germany
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4
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Hashem Y, Foust K, Kaledin M, Kaledin AL. Fitting Potential Energy Surfaces by Learning the Charge Density Matrix with Permutationally Invariant Polynomials. J Chem Theory Comput 2023; 19:5690-5700. [PMID: 37561135 PMCID: PMC10501011 DOI: 10.1021/acs.jctc.3c00586] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/01/2023] [Indexed: 08/11/2023]
Abstract
The electronic energy in the Hartree-Fock (HF) theory is the trace of the product of the charge density matrix (CDM) with the one-electron and two-electron matrices represented in an atomic orbital basis, where the two-electron matrix is also a function of the same CDM. In this work, we examine a formalism of analytic representation of a generic molecular potential energy surface (PES) as a sum of a linearly parameterized HF and a correction term, the latter formally representing the electron correlation energy, also linearly parameterized, by expressing the elements of CDM using permutationally invariant polynomials (PIPs). We show on a variety of numerical examples, ranging from exemplary two-electron systems HeH+ and H3+ to the more challenging cases of methanium (CH5+) fragmentation and high-energy tautomerization of formamide to formimidic acid that such a formulation requires significantly fewer, 10-20% of PIPs, to accomplish the same accuracy of the fit as the conventional representation at practically the same computational cost.
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Affiliation(s)
- Younos Hashem
- Department
of Chemistry & Biochemistry, Kennesaw
State University, 370 Paulding Ave NW, Box # 1203, Kennesaw 30144, Georgia
| | - Katheryn Foust
- Department
of Chemistry & Biochemistry, Kennesaw
State University, 370 Paulding Ave NW, Box # 1203, Kennesaw 30144, Georgia
| | - Martina Kaledin
- Department
of Chemistry & Biochemistry, Kennesaw
State University, 370 Paulding Ave NW, Box # 1203, Kennesaw 30144, Georgia
| | - Alexey L. Kaledin
- Cherry
L. Emerson Center for Scientific Computation and Department of Chemistry, Emory University, 1515 Dickey Drive, Atlanta 30322, Georgia
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5
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Riera M, Knight C, Bull-Vulpe EF, Zhu X, Agnew H, Smith DGA, Simmonett AC, Paesani F. MBX: A many-body energy and force calculator for data-driven many-body simulations. J Chem Phys 2023; 159:054802. [PMID: 37526156 PMCID: PMC10550339 DOI: 10.1063/5.0156036] [Citation(s) in RCA: 11] [Impact Index Per Article: 11.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/25/2023] [Accepted: 07/11/2023] [Indexed: 08/02/2023] Open
Abstract
Many-Body eXpansion (MBX) is a C++ library that implements many-body potential energy functions (PEFs) within the "many-body energy" (MB-nrg) formalism. MB-nrg PEFs integrate an underlying polarizable model with explicit machine-learned representations of many-body interactions to achieve chemical accuracy from the gas to the condensed phases. MBX can be employed either as a stand-alone package or as an energy/force engine that can be integrated with generic software for molecular dynamics and Monte Carlo simulations. MBX is parallelized internally using Open Multi-Processing and can utilize Message Passing Interface when available in interfaced molecular simulation software. MBX enables classical and quantum molecular simulations with MB-nrg PEFs, as well as hybrid simulations that combine conventional force fields and MB-nrg PEFs, for diverse systems ranging from small gas-phase clusters to aqueous solutions and molecular fluids to biomolecular systems and metal-organic frameworks.
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Affiliation(s)
- Marc Riera
- Department of Chemistry and Biochemistry, University of California San Diego, La Jolla, California 92093, USA
| | - Christopher Knight
- Argonne National Laboratory, Computational Science Division, Lemont, Illinois 60439, USA
| | - Ethan F. Bull-Vulpe
- Department of Chemistry and Biochemistry, University of California San Diego, La Jolla, California 92093, USA
| | - Xuanyu Zhu
- Department of Chemistry and Biochemistry, University of California San Diego, La Jolla, California 92093, USA
| | - Henry Agnew
- Department of Chemistry and Biochemistry, University of California San Diego, La Jolla, California 92093, USA
| | | | - Andrew C. Simmonett
- Laboratory of Computational Biology, National Heart, Lung and Blood Institute, National Institutes of Health, Bethesda, Maryland 20892, USA
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6
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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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7
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Houston PL, Qu C, Yu Q, Conte R, Nandi A, Li JK, Bowman JM. PESPIP: Software to fit complex molecular and many-body potential energy surfaces with permutationally invariant polynomials. J Chem Phys 2023; 158:044109. [PMID: 36725524 DOI: 10.1063/5.0134442] [Citation(s) in RCA: 12] [Impact Index Per Article: 12.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/05/2023] Open
Abstract
We wish to describe a potential energy surface by using a basis of permutationally invariant polynomials whose coefficients will be determined by numerical regression so as to smoothly fit a dataset of electronic energies as well as, perhaps, gradients. The polynomials will be powers of transformed internuclear distances, usually either Morse variables, exp(-ri,j/λ), where λ is a constant range hyperparameter, or reciprocals of the distances, 1/ri,j. The question we address is how to create the most efficient basis, including (a) which polynomials to keep or discard, (b) how many polynomials will be needed, (c) how to make sure the polynomials correctly reproduce the zero interaction at a large distance, (d) how to ensure special symmetries, and (e) how to calculate gradients efficiently. This article discusses how these questions can be answered by using a set of programs to choose and manipulate the polynomials as well as to write efficient Fortran programs for the calculation of energies and gradients. A user-friendly interface for access to monomial symmetrization approach results is also described. The software for these programs is now publicly available.
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Affiliation(s)
- Paul L Houston
- Department of Chemistry and Chemical Biology, Cornell University, Ithaca, New York 14853, USA and Department of Chemistry and Biochemistry, Georgia Institute of Technology, Atlanta, Georgia 30332, USA
| | - Chen Qu
- Independent Researcher, Toronto, Ontario M9B0E3, Canada
| | - Qi Yu
- Department of Chemistry, Yale University, New Haven, Connecticut 06520, USA
| | - Riccardo Conte
- Dipartimento di Chimica, Università Degli Studi di Milano, Via Golgi 19, 20133 Milano, Italy
| | - Apurba Nandi
- Department of Chemistry and Cherry L. Emerson Center for Scientific Computation, Emory University, Atlanta, Georgia 30322, USA
| | - Jeffrey K Li
- Department of Chemistry and Cherry L. Emerson Center for Scientific Computation, Emory University, Atlanta, Georgia 30322, USA
| | - Joel M Bowman
- Department of Chemistry and Cherry L. Emerson Center for Scientific Computation, Emory University, Atlanta, Georgia 30322, USA
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8
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Bull-Vulpe EF, Riera M, Bore SL, Paesani F. Data-Driven Many-Body Potential Energy Functions for Generic Molecules: Linear Alkanes as a Proof-of-Concept Application. J Chem Theory Comput 2022. [PMID: 36113028 DOI: 10.1021/acs.jctc.2c00645] [Citation(s) in RCA: 11] [Impact Index Per Article: 5.5] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/28/2022]
Abstract
We present a generalization of the many-body energy (MB-nrg) theoretical/computational framework that enables the development of data-driven potential energy functions (PEFs) for generic covalently bonded molecules, with arbitrary quantum mechanical accuracy. The "nearsightedness of electronic matter" is exploited to define monomers as "natural building blocks" on the basis of their distinct chemical identity. The energy of generic molecules is then expressed as a sum of individual many-body energies of incrementally larger subsystems. The MB-nrg PEFs represent the low-order n-body energies, with n = 1-4, using permutationally invariant polynomials derived from electronic structure data carried out at an arbitrary quantum mechanical level of theory, while all higher-order n-body terms (n > 4) are represented by a classical many-body polarization term. As a proof-of-concept application of the general MB-nrg framework, we present MB-nrg PEFs for linear alkanes. The MB-nrg PEFs are shown to accurately reproduce reference energies, harmonic frequencies, and potential energy scans of alkanes, independently of their length. Since, by construction, the MB-nrg framework introduced here can be applied to generic covalently bonded molecules, we envision future computer simulations of complex molecular systems using data-driven MB-nrg PEFs, with arbitrary quantum mechanical accuracy.
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Affiliation(s)
- Ethan F. Bull-Vulpe
- Department of Chemistry and Biochemistry, University of California San Diego, La Jolla, California 92093, United States
| | - Marc Riera
- Department of Chemistry and Biochemistry, University of California San Diego, La Jolla, California 92093, United States
| | - Sigbjørn L. Bore
- Department of Chemistry and Biochemistry, University of California San Diego, La Jolla, California 92093, United States
| | - Francesco Paesani
- Department of Chemistry and Biochemistry, University of California San Diego, La Jolla, California 92093, United States
- Materials Science and Engineering, University of California San Diego, La Jolla, California 92093, United States
- San Diego Supercomputer Center, University of California San Diego, La Jolla, California 92093, United States
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9
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Chen A, Benoit DM, Scribano Y, Nauts A, Lauvergnat D. Smolyak Algorithm Adapted to a System-Bath Separation: Application to an Encapsulated Molecule with Large-Amplitude Motions. J Chem Theory Comput 2022; 18:4366-4372. [PMID: 35584357 DOI: 10.1021/acs.jctc.2c00108] [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
A Smolyak algorithm adapted to system-bath separation is proposed for rigorous quantum simulations. This technique combines a sparse grid method with the system-bath concept in a specific configuration without limitations on the form of the Hamiltonian, thus achieving a highly efficient convergence of the excitation transitions for the "system" part. Our approach provides a general way to overcome the perennial convergence problem for the standard Smolyak algorithm and enables the simulation of floppy molecules with more than a hundred degrees of freedom. The efficiency of the present method is illustrated on the simulation of H2 caged in an sII clathrate hydrate including two kinds of cage modes. The transition energies are converged by increasing the number of normal modes of water molecules. Our results confirm the triplet splittings of both translational and rotational (j = 1) transitions of the H2 molecule. Furthermore, they show a slight increase of the translational transitions with respect to the ones in a rigid cage.
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Affiliation(s)
- Ahai Chen
- Maison de la Simulation, UVSQ, CNRS, CEA, Université Paris-Saclay, 91191 Gif-sur-Yvette, France.,Institut de Chimie Physique, UMR-CNRS 8000, Université Paris-Saclay, CNRS, 91405 Orsay, France
| | - David M Benoit
- E.A. Milne Centre for Astrophysics, The University of Hull, Cottingham Road, Kingston upon Hull HU6 7RX, U.K
| | - Yohann Scribano
- Laboratoire Univers et Particules de Montpellier, UMR-CNRS 5299, Université de Montpellier, 34095 Montpellier Cedex, France
| | - André Nauts
- Institut de Chimie Physique, UMR-CNRS 8000, Université Paris-Saclay, CNRS, 91405 Orsay, France.,Institute of Condensed Matter and Nanosciences (NAPS), Université Catholique de Louvain, 1348 Louvain-la-Neuve, Belgium
| | - David Lauvergnat
- Institut de Chimie Physique, UMR-CNRS 8000, Université Paris-Saclay, CNRS, 91405 Orsay, France
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10
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Schmidt M, Roy PN. On the accuracy and efficiency of different methods to calculate Raman vibrational shifts of parahydrogen clusters. J Chem Phys 2022; 156:084102. [DOI: 10.1063/5.0076403] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/14/2022] Open
Abstract
The Raman vibrational frequency shifts of pure parahydrogen and orthodeuterium clusters of sizes N = 4–9 are calculated using the Langevin equation path integral ground state method. The shifts are calculated using three different methods; the results obtained from each are compared to experiment and variance properties are assessed. The first method requires the direct calculation of energies from two simulations: one when the cluster is in the v = 0 vibrational state and one when the cluster has v = 1 total quantum of vibration. The shift is directly calculated from the difference in those two energies. The second method requires only a v = 0 simulation to be performed. The ground state energy is calculated as usual and the excited state energy is calculated by using the distribution of the v = 0 simulation and the ratio of the density matrices between the v = 1 state and the v = 0 state. The shift is calculated from the difference in those two energies. These first two are both exact methods. The final method is based on perturbation theory where the shift is calculated by averaging the pairwise difference potential over the pair distribution function. However, this is an approximate approach. It is found that for large enough system sizes, despite the approximations, the perturbation theory method has the strongest balance between accuracy and precision when weighing against computational cost.
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Affiliation(s)
- Matthew Schmidt
- Department of Chemistry, University of Waterloo, Waterloo, Ontario N2L 3G1, Canada
| | - Pierre-Nicholas Roy
- Department of Chemistry, University of Waterloo, Waterloo, Ontario N2L 3G1, Canada
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11
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Houston PL, Qu C, Nandi A, Conte R, Yu Q, Bowman JM. Permutationally invariant polynomial regression for energies and gradients, using reverse differentiation, achieves orders of magnitude speed-up with high precision compared to other machine learning methods. J Chem Phys 2022; 156:044120. [DOI: 10.1063/5.0080506] [Citation(s) in RCA: 7] [Impact Index Per Article: 3.5] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/28/2022] Open
Affiliation(s)
- Paul L. Houston
- Department of Chemistry and Chemical Biology, Cornell University, Ithaca, New York 14853, USA and Department of Chemistry and Biochemistry, Georgia Institute of Technology, Atlanta, Georgia 30332, USA
| | - Chen Qu
- Department of Chemistry and Biochemistry, University of Maryland, College Park, Maryland 20742, USA
| | - Apurba Nandi
- Department of Chemistry and Cherry L. Emerson Center for Scientific Computation, Emory University, Atlanta, Georgia 30322, USA
| | - Riccardo Conte
- Dipartimento di Chimica, Università Degli Studi di Milano, via Golgi 19, 20133 Milano, Italy
| | - Qi Yu
- Department of Chemistry, Yale University, New Haven, Connecticut 06511, USA
| | - Joel M. Bowman
- Department of Chemistry and Cherry L. Emerson Center for Scientific Computation, Emory University, Atlanta, Georgia 30322, USA
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12
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Nandi A, Qu C, Houston PL, Conte R, Yu Q, Bowman JM. A CCSD(T)-Based 4-Body Potential for Water. J Phys Chem Lett 2021; 12:10318-10324. [PMID: 34662138 DOI: 10.1021/acs.jpclett.1c03152] [Citation(s) in RCA: 22] [Impact Index Per Article: 7.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 06/13/2023]
Abstract
High-level, ab initio calculations find that the 4-body (4-b) interaction is needed to account for near-100% of the total interaction energy for water clusters as large as the 21-mer. Motivated by this, we report a permutationally invariant polynomial potential energy surface (PES) for the 4-body interaction. This machine-learned PES is a fit to 2119 symmetry-unique, CCSD(T)-F12a/haTZ 4-b interaction energies. Configurations for these come from tetramer direct-dynamics calculations, fragments from an MD water simulation at 300 K, and tetramer fragments in a variety of water clusters. The PIP basis is purified to ensure that the PES goes rigorously to zero in monomer+trimer and dimer+dimer dissociations. The 4-b energies of isomers of the hexamer calculated with the new PES are shown to be in better agreement with benchmark CCSD(T) results than those from the MB-pol potential. Tests on larger clusters further validate the high-fidelity of the PES. The PES is shown to be fast to evaluate, taking 2.4 s for 105 evaluations on a single core of 2.4 GHz Intel Xeon processor, and significantly faster using a parallel version of the PES.
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Affiliation(s)
- Apurba Nandi
- Department of Chemistry and Cherry L. Emerson Center for Scientific Computation, Emory University, Atlanta, Georgia 30322, United States
| | - Chen Qu
- Department of Chemistry & Biochemistry, University of Maryland, College Park, Maryland 20742, United States
| | - Paul L Houston
- Department of Chemistry and Chemical Biology, Cornell University, Ithaca, New York 14853, United States
- Department of Chemistry and Biochemistry, Georgia Institute of Technology, Atlanta, Georgia 30332, United States
| | - Riccardo Conte
- Dipartimento di Chimica, Università Degli Studi di Milano, via Golgi 19, 20133 Milano, Italy
| | - Qi Yu
- Department of Chemistry, Yale University, New Haven, Connecticut 06520, United States
| | - Joel M Bowman
- Department of Chemistry and Cherry L. Emerson Center for Scientific Computation, Emory University, Atlanta, Georgia 30322, United States
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13
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Hellmann R, Harvey AH. First-Principles Diffusivity Ratios for Atmospheric Isotope Fractionation on Mars and Titan. JOURNAL OF GEOPHYSICAL RESEARCH. PLANETS 2021; 126:10.1029/2021je006857. [PMID: 34849323 PMCID: PMC8628554 DOI: 10.1029/2021je006857] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Received: 02/09/2021] [Accepted: 03/25/2021] [Indexed: 06/13/2023]
Abstract
Recent work used the kinetic theory of molecular gases, along with state-of-the-art intermolecular potentials, to calculate from first principles the diffusivity ratios necessary for modeling kinetic fractionation of water isotopes in air. Here, we extend that work to the Martian atmosphere, employing potential-energy surfaces for the interaction of water with carbon dioxide and with nitrogen. We also derive diffusivity ratios for methane isotopes in the atmosphere of Titan by using a high-quality potential for the methane-nitrogen pair. The Mars calculations cover 100 K to 400 K, while the Titan calculations cover 50 K to 200 K. Surprisingly, the simple hard-sphere theory that is inaccurate for Earth's atmosphere is in good agreement with the rigorous results for the diffusion of water isotopes in the Martian atmosphere. A modest disagreement with the hard-sphere results is observed for the diffusivity ratio of CH3D in the atmosphere of Titan. We present temperature-dependent correlations, as well as estimates of uncertainty, for the diffusivity ratios involving HDO, H2 17O, and H2 18O in the Martian atmosphere, and for CH3D and 13CH4 in the atmosphere of Titan, providing for the first time the necessary data to be able to model kinetic isotope fractionation in these environments.
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Affiliation(s)
- Robert Hellmann
- Institut für Thermodynamik, Helmut-Schmidt-Universität / Universität der Bundeswehr Hamburg, Holstenhofweg 85, 22043 Hamburg, Germany
| | - Allan H. Harvey
- Applied Chemicals and Materials Division, National Institute of Standards and Technology, 325 Broadway, Boulder, Colorado 80305, U.S.A
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14
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Cendagorta JR, Shen H, Bačić Z, Tuckerman ME. Enhanced Sampling Path Integral Methods Using Neural Network Potential Energy Surfaces with Application to Diffusion in Hydrogen Hydrates. ADVANCED THEORY AND SIMULATIONS 2020. [DOI: 10.1002/adts.202000258] [Citation(s) in RCA: 6] [Impact Index Per Article: 1.5] [Reference Citation Analysis] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 12/18/2022]
Affiliation(s)
| | - Hengyuan Shen
- Department of Chemistry New York University Shanghai 1555 Century Avenue Pudong Shanghai 200122 China
| | - Zlatko Bačić
- Department of Chemistry New York University New York NY 10003 USA
- NYU‐ECNU Center for Computational Chemistry at NYU Shanghai 3663 Zhongshan Road, North Shanghai 200062 China
| | - Mark E. Tuckerman
- Department of Chemistry New York University New York NY 10003 USA
- NYU‐ECNU Center for Computational Chemistry at NYU Shanghai 3663 Zhongshan Road, North Shanghai 200062 China
- Courant Institute of Mathematical Sciences New York University New York NY 10012 USA
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15
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Bergeat A, Faure A, Morales SB, Moudens A, Naulin C. Low-Energy Water-Hydrogen Inelastic Collisions. J Phys Chem A 2020; 124:259-264. [PMID: 31283233 DOI: 10.1021/acs.jpca.9b04753] [Citation(s) in RCA: 6] [Impact Index Per Article: 1.5] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/28/2022]
Abstract
New molecular beam scattering experiments are reported for the water-hydrogen system. Integral cross sections of the first rotational excitations of para- and ortho-H2O by inelastic collisions with normal-H2 were determined by crossing a beam of H2O seeded in He with a beam of H2. H2O and H2 were cooled in the supersonic expansion down to their lowest rotational levels. Crossed-beam scattering experiments were performed at collision energies from 15 cm-1 (below the threshold for the excitation to the lowest excited rotational state of H2O: 18.6 cm-1) up to 105 cm-1 by varying the beam crossing angle. The measured state-to-state cross-sections were compared to the theoretical cross-sections (close-coupling quantum scattering calculations): the good agreement found further validates both the employed potential energy surface describing the H2O-H2 van der Waals interaction and the state-to-state rate coefficients calculated with this potential in the very low temperature range needed for the modeling of interstellar media.
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Affiliation(s)
- Astrid Bergeat
- Univ. Bordeaux , CNRS, Bordeaux INP, ISM , UMR 5255, F-33405 Talence , France
| | - Alexandre Faure
- Univ. Grenoble Alpes , CNRS, IPAG , F-38000 Grenoble , France
| | - Sébastien B Morales
- Univ. Bordeaux , CNRS, Bordeaux INP, ISM , UMR 5255, F-33405 Talence , France
| | - Audrey Moudens
- Univ. Bordeaux , CNRS, Bordeaux INP, ISM , UMR 5255, F-33405 Talence , France
| | - Christian Naulin
- Univ. Bordeaux , CNRS, Bordeaux INP, ISM , UMR 5255, F-33405 Talence , France
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16
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Felker PM, Lauvergnat D, Scribano Y, Benoit DM, Bačić Z. Intramolecular stretching vibrational states and frequency shifts of (H2)2 confined inside the large cage of clathrate hydrate from an eight-dimensional quantum treatment using small basis sets. J Chem Phys 2019; 151:124311. [DOI: 10.1063/1.5124051] [Citation(s) in RCA: 20] [Impact Index Per Article: 4.0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/14/2022] Open
Affiliation(s)
- Peter M. Felker
- Department of Chemistry and Biochemistry, University of California, Los Angeles, California 90095-1569, USA
| | - David Lauvergnat
- Laboratoire de Chimie Physique, UMR-CNRS 8000, Université de Paris-Sud, Orsay F-91405, France
| | - Yohann Scribano
- Laboratoire Univers et Particule de Montpellier, Université de Montpellier, UMR-CNRS 5299, 34095 Montpellier Cedex, France
| | - David M. Benoit
- Department of Physics and Mathematics, E. A. Milne Centre for Astrophysics and G. W. Gray Centre for Advanced Materials, The University of Hull, Cottingham Road, Kingston upon Hull HU6 7RX, United Kingdom
| | - Zlatko Bačić
- Department of Chemistry, New York University, New York, New York 10003, USA
- NYU-ECNU Center for Computational Chemistry at NYU Shanghai, 3663 Zhongshan Road North, Shanghai 200062, China
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17
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Lauvergnat D, Felker P, Scribano Y, Benoit DM, Bačić Z. H2, HD, and D2in the small cage of structure II clathrate hydrate: Vibrational frequency shifts from fully coupled quantum six-dimensional calculations of the vibration-translation-rotation eigenstates. J Chem Phys 2019; 150:154303. [DOI: 10.1063/1.5090573] [Citation(s) in RCA: 21] [Impact Index Per Article: 4.2] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/14/2022] Open
Affiliation(s)
- David Lauvergnat
- Laboratoire de Chimie Physique, UMR-CNRS 8000, Université de Paris-Sud, Orsay F-91405, France
| | - Peter Felker
- Department of Chemistry and Biochemistry, University of California, Los Angeles, California 90095-1569, USA
| | - Yohann Scribano
- Laboratoire Univers et Particules de Montpellier, Université de Montpellier, UMR-CNRS 5299, 34095 Montpellier Cedex, France
| | - David M. Benoit
- Department of Physics and Mathematics, E.A. Milne Centre for Astrophysics and G. W. Gray Centre for Advanced Materials, The University of Hull, Cottingham Road, Kingston upon Hull HU6 7RX, United Kingdom
| | - Zlatko Bačić
- Department of Chemistry, New York University, New York, New York 10003, USA
- NYU-ECNU Center for Computational Chemistry at NYU Shanghai, 3663 Zhongshan Road North, Shanghai, 200062, China
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18
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Qu C, Bowman JM. Assessing the Importance of the H 2-H 2O-H 2O Three-Body Interaction on the Vibrational Frequency Shift of H 2 in the sII Clathrate Hydrate and Comparison with Experiment. J Phys Chem A 2019; 123:329-335. [PMID: 30525619 DOI: 10.1021/acs.jpca.8b11675] [Citation(s) in RCA: 7] [Impact Index Per Article: 1.4] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/28/2022]
Abstract
The vibrational frequency shift of H2 in the 512 cage of the sII clathrate hydrate with and without surrounding water molecules is reported at 0 K, using diffusion Monte Carlo calculations for the ground and first excited vibrational states of H2. Approximate 1d calculations of the frequency shift are also reported with the H2 at the equilibrium position in the clathrate hydrate. These calculations make use of full-dimensional potential energy surfaces for the H2-H2O 2-body and H2-H2O-H2O 3-body interactions. The inclusion of the 3-body interaction is shown to make roughly a 33% contribution to the frequency shift and to bring the calculated value of -40 ± 4 cm-1 to within just 3 cm-1 of the experimental value at 20 K. This level of agreement with experiment may be somewhat fortuitous; however, the importance of the 3-body interaction is firmly established by these calculations. The frequency shift reported here with 2-body interactions does not agree with a previously reported calculation using just 2-body interactions from a different ab initio potential energy surface and with a different method to obtain the frequency shift. A similar 1d calculation of the frequency shift using that potential is reported and agrees to within roughly 10% of the one previously reported. Therefore, this suggests that the difference between the present calculations and the previous one using just 2-body interactions is mainly due to differences in the potential energy surfaces.
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Affiliation(s)
- Chen Qu
- Cherry L. Emerson Center for Scientifc Computations and Department of Chemistry , Emory University , Atlanta , Georgia 30322 , United States
| | - Joel M Bowman
- Cherry L. Emerson Center for Scientifc Computations and Department of Chemistry , Emory University , Atlanta , Georgia 30322 , United States
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19
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Qu C, Bowman JM. Quantum approaches to vibrational dynamics and spectroscopy: is ease of interpretation sacrificed as rigor increases? Phys Chem Chem Phys 2019; 21:3397-3413. [DOI: 10.1039/c8cp04990d] [Citation(s) in RCA: 25] [Impact Index Per Article: 5.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/09/2023]
Abstract
The subject of this Perspective is quantum approaches, beyond the harmonic approximation, to vibrational dynamics and IR spectroscopy.
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Affiliation(s)
- Chen Qu
- Department of Chemistry and Cherry L. Emerson Center for Scientific Computation, Emory University
- Atlanta
- USA
| | - Joel M. Bowman
- Department of Chemistry and Cherry L. Emerson Center for Scientific Computation, Emory University
- Atlanta
- USA
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20
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Wang H, Bettens RPA. Modelling potential energy surfaces for small clusters using Shepard interpolation with Gaussian-form nodal functions. Phys Chem Chem Phys 2019; 21:4513-4522. [DOI: 10.1039/c8cp07640e] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.6] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/21/2022]
Abstract
A new interpolation method based on Gaussian functions to reliably generate potential energy surfaces.
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Affiliation(s)
- Haina Wang
- Department of Chemistry
- Princeton University
- Princeton
- USA
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21
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Intermolecular rovibrational bound states of H2O H2 dimer from a MultiConfiguration Time Dependent Hartree approach. Chem Phys Lett 2019. [DOI: 10.1016/j.cplett.2018.11.035] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.6] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/29/2022]
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22
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Di Liberto G, Conte R, Ceotto M. "Divide and conquer" semiclassical molecular dynamics: A practical method for spectroscopic calculations of high dimensional molecular systems. J Chem Phys 2018; 148:014307. [PMID: 29306274 DOI: 10.1063/1.5010388] [Citation(s) in RCA: 30] [Impact Index Per Article: 5.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 02/04/2023] Open
Abstract
We extensively describe our recently established "divide-and-conquer" semiclassical method [M. Ceotto, G. Di Liberto, and R. Conte, Phys. Rev. Lett. 119, 010401 (2017)] and propose a new implementation of it to increase the accuracy of results. The technique permits us to perform spectroscopic calculations of high-dimensional systems by dividing the full-dimensional problem into a set of smaller dimensional ones. The partition procedure, originally based on a dynamical analysis of the Hessian matrix, is here more rigorously achieved through a hierarchical subspace-separation criterion based on Liouville's theorem. Comparisons of calculated vibrational frequencies to exact quantum ones for a set of molecules including benzene show that the new implementation performs better than the original one and that, on average, the loss in accuracy with respect to full-dimensional semiclassical calculations is reduced to only 10 wavenumbers. Furthermore, by investigating the challenging Zundel cation, we also demonstrate that the "divide-and-conquer" approach allows us to deal with complex strongly anharmonic molecular systems. Overall the method very much helps the assignment and physical interpretation of experimental IR spectra by providing accurate vibrational fundamentals and overtones decomposed into reduced dimensionality spectra.
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Affiliation(s)
- Giovanni Di Liberto
- Dipartimento di Chimica, Università degli Studi di Milano, Via C. Golgi 19, 20133 Milano, Italy
| | - Riccardo Conte
- Dipartimento di Chimica, Università degli Studi di Milano, Via C. Golgi 19, 20133 Milano, Italy
| | - Michele Ceotto
- Dipartimento di Chimica, Università degli Studi di Milano, Via C. Golgi 19, 20133 Milano, Italy
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23
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Affiliation(s)
- Chen Qu
- Department of Chemistry, Cherry L. Emerson Center for Scientific Computation, Emory University, Atlanta, Georgia 30322, USA
| | - Qi Yu
- Department of Chemistry, Cherry L. Emerson Center for Scientific Computation, Emory University, Atlanta, Georgia 30322, USA
| | - Joel M. Bowman
- Department of Chemistry, Cherry L. Emerson Center for Scientific Computation, Emory University, Atlanta, Georgia 30322, USA
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24
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Powers A, Scribano Y, Lauvergnat D, Mebe E, Benoit DM, Bačić Z. The effect of the condensed-phase environment on the vibrational frequency shift of a hydrogen molecule inside clathrate hydrates. J Chem Phys 2018; 148:144304. [DOI: 10.1063/1.5024884] [Citation(s) in RCA: 13] [Impact Index Per Article: 2.2] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/14/2022] Open
Affiliation(s)
- Anna Powers
- Department of Chemistry, New York University, New York, New York 10003, USA
| | - Yohann Scribano
- Laboratoire Univers et Particules de Montpellier, Université de Montpellier, LUPM-UMR CNRS 5299, 34095 Montpellier Cedex, France
| | - David Lauvergnat
- Laboratoire de Chimie Physique UMR CNRS 8000-Université de Paris-Sud, Orsay F-91405, France
| | - Elsy Mebe
- Laboratoire de Chimie Physique UMR CNRS 8000-Université de Paris-Sud, Orsay F-91405, France
| | - David M. Benoit
- E.A. Milne Centre for Astrophysics & G.W. Gray Centre for Advanced Materials, Chemistry, The University of Hull, Cottingham Road, Kingston upon Hull HU6 7RX, United Kingdom
| | - Zlatko Bačić
- Department of Chemistry, New York University, New York, New York 10003, USA
- NYU-ECNU Center for Computational Chemistry at NYU Shanghai, 3663 Zhongshan Road North, Shanghai 200062, China
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25
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Buchholz M, Grossmann F, Ceotto M. Simplified approach to the mixed time-averaging semiclassical initial value representation for the calculation of dense vibrational spectra. J Chem Phys 2018; 148:114107. [DOI: 10.1063/1.5020144] [Citation(s) in RCA: 31] [Impact Index Per Article: 5.2] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/14/2022] Open
Affiliation(s)
- Max Buchholz
- Dipartimento di Chimica, Università degli Studi di Milano, Via C. Golgi 19, 20133 Milano, Italy
| | - Frank Grossmann
- Institut für Theoretische Physik, Technische Universität Dresden, 01062 Dresden, Germany
| | - Michele Ceotto
- Dipartimento di Chimica, Università degli Studi di Milano, Via C. Golgi 19, 20133 Milano, Italy
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26
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Di Liberto G, Conte R, Ceotto M. “Divide-and-conquer” semiclassical molecular dynamics: An application to water clusters. J Chem Phys 2018; 148:104302. [DOI: 10.1063/1.5023155] [Citation(s) in RCA: 28] [Impact Index Per Article: 4.7] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/15/2022] Open
Affiliation(s)
- Giovanni Di Liberto
- Dipartimento di Chimica, Università degli Studi di Milano, Via C. Golgi 19, 20133 Milano, Italy
| | - Riccardo Conte
- Dipartimento di Chimica, Università degli Studi di Milano, Via C. Golgi 19, 20133 Milano, Italy
| | - Michele Ceotto
- Dipartimento di Chimica, Università degli Studi di Milano, Via C. Golgi 19, 20133 Milano, Italy
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27
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Wang Q(K, Bowman JM. Two-component, ab initio potential energy surface for CO2—H2O, extension to the hydrate clathrate, CO2@(H2O)20, and VSCF/VCI vibrational analyses of both. J Chem Phys 2017; 147:161714. [DOI: 10.1063/1.4994543] [Citation(s) in RCA: 20] [Impact Index Per Article: 2.9] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/09/2023] Open
Affiliation(s)
- Qingfeng (Kee) Wang
- Department of Chemistry and Cherry L. Emerson Center for Scientific Computation, Emory University, Atlanta, Georgia 30322, USA
| | - Joel M. Bowman
- Department of Chemistry and Cherry L. Emerson Center for Scientific Computation, Emory University, Atlanta, Georgia 30322, USA
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28
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Thomsen B, Kawakami T, Shigemoto I, Sugita Y, Yagi K. Weight-Averaged Anharmonic Vibrational Analysis of Hydration Structures of Polyamide 6. J Phys Chem B 2017; 121:6050-6063. [DOI: 10.1021/acs.jpcb.7b00372] [Citation(s) in RCA: 10] [Impact Index Per Article: 1.4] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/28/2022]
Affiliation(s)
- Bo Thomsen
- Theoretical
Molecular Science Laboratory, RIKEN, 2-1 Hirosawa, Wako, Saitama 351-0198, Japan
| | - Tomonori Kawakami
- Advanced
Materials Research Laboratories, Toray Industries, Inc., 2-1 Sonoyama 3-chome, Otsu, Shiga 520-0842, Japan
| | - Isamu Shigemoto
- Advanced
Materials Research Laboratories, Toray Industries, Inc., 2-1 Sonoyama 3-chome, Otsu, Shiga 520-0842, Japan
| | - Yuji Sugita
- Theoretical
Molecular Science Laboratory, RIKEN, 2-1 Hirosawa, Wako, Saitama 351-0198, Japan
- RIKEN iTHES, 2-1 Hirosawa, Wako, Saitama 351-0198, Japan
- RIKEN Advanced Institute for Computational Science, 7-1-26 Minatojima-Minamimachi,
Chuo-ku, Kobe, Hyogo 650-0047, Japan
- RIKEN Quantitative Biology Center, 6-7-1 Minatojima-Minamimachi, Chuo-ku, Kobe, Hyogo 650-0047, Japan
| | - Kiyoshi Yagi
- Theoretical
Molecular Science Laboratory, RIKEN, 2-1 Hirosawa, Wako, Saitama 351-0198, Japan
- RIKEN iTHES, 2-1 Hirosawa, Wako, Saitama 351-0198, Japan
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29
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Aieta C, Ceotto M. A quantum method for thermal rate constant calculations from stationary phase approximation of the thermal flux-flux correlation function integral. J Chem Phys 2017; 146:214115. [DOI: 10.1063/1.4984099] [Citation(s) in RCA: 10] [Impact Index Per Article: 1.4] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/14/2022] Open
Affiliation(s)
- Chiara Aieta
- Dipartimento di Chimica, Università degli Studi di Milano, Via C. Golgi 19, 20133 Milano, Italy
| | - Michele Ceotto
- Dipartimento di Chimica, Università degli Studi di Milano, Via C. Golgi 19, 20133 Milano, Italy
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30
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Gabas F, Conte R, Ceotto M. On-the-Fly ab Initio Semiclassical Calculation of Glycine Vibrational Spectrum. J Chem Theory Comput 2017; 13:2378-2388. [PMID: 28489368 PMCID: PMC5472367 DOI: 10.1021/acs.jctc.6b01018] [Citation(s) in RCA: 49] [Impact Index Per Article: 7.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/29/2022]
Abstract
![]()
We
present an on-the-fly ab initio semiclassical study of vibrational
energy levels of glycine, calculated by Fourier transform of the wavepacket
correlation function. It is based on a multiple coherent states approach
integrated with monodromy matrix regularization for chaotic dynamics.
All four lowest-energy glycine conformers are investigated by means
of single-trajectory semiclassical spectra obtained upon classical
evolution of on-the-fly trajectories with harmonic zero-point energy.
For the most stable conformer I, direct dynamics trajectories are
also run for each vibrational mode with energy equal to the first
harmonic excitation. An analysis of trajectories evolved up to 50 000
atomic time units demonstrates that, in this time span, conformers
II and III can be considered as isolated species, while conformers
I and IV show a pretty facile interconversion. Therefore, previous
perturbative studies based on the assumption of isolated conformers
are often reliable but might be not completely appropriate in the
case of conformer IV and conformer I for which interconversion occurs
promptly.
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Affiliation(s)
- Fabio Gabas
- Dipartimento di Chimica, Università degli Studi di Milano , via Golgi 19, 20133 Milano, Italy
| | - Riccardo Conte
- Dipartimento di Chimica, Università degli Studi di Milano , via Golgi 19, 20133 Milano, Italy
| | - Michele Ceotto
- Dipartimento di Chimica, Università degli Studi di Milano , via Golgi 19, 20133 Milano, Italy
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31
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Ling H, Xia M, Chen W, Chai Z, Wang D. Influence of denticity and combined soft–hard strategy on the interaction of picolinic-type ligands with NpO2+. RSC Adv 2017. [DOI: 10.1039/c6ra26114k] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.1] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/21/2022] Open
Abstract
The denticity of the ligands and the combined hard–soft donor strategy work cooperatively in the coordination of NpO2+ with ligands.
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Affiliation(s)
- Hongcai Ling
- College of Chemistry
- Fuzhou University
- Fuzhou 350116
- P. R. China
- Multidisciplinary Initiative Center
| | - Miaoren Xia
- Multidisciplinary Initiative Center
- Institute of High Energy Physics
- Chinese Academy of Sciences
- Beijing 100049
- P. R. China
| | - Wenkai Chen
- College of Chemistry
- Fuzhou University
- Fuzhou 350116
- P. R. China
- Key Laboratory of Applied Nuclear Techniques in Geosciences Sichuan
| | - Zhifang Chai
- Multidisciplinary Initiative Center
- Institute of High Energy Physics
- Chinese Academy of Sciences
- Beijing 100049
- P. R. China
| | - Dongqi Wang
- Multidisciplinary Initiative Center
- Institute of High Energy Physics
- Chinese Academy of Sciences
- Beijing 100049
- P. R. China
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32
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Hjertenæs E, Trinh TT, Koch H. Chemically accurate energy barriers of small gas molecules moving through hexagonal water rings. Phys Chem Chem Phys 2016; 18:17831-5. [PMID: 27345929 DOI: 10.1039/c6cp02651f] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/21/2022]
Abstract
We present chemically accurate potential energy curves of CH4, CO2 and H2 moving through hexagonal water rings, calculated by CCSD(T)/aug-cc-pVTZ with counterpoise correction. The barriers are extracted from a potential energy surface obtained by allowing the water ring to expand while the gas molecule diffuses through. State-of-the-art XC-functionals are evaluated against the CCSD(T) potential energy surface.
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Affiliation(s)
- Eirik Hjertenæs
- Department of Chemistry, NTNU-Norwegian University of Science and Technology, Høgskoleringen 5, 7491-Trondheim, Norway.
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33
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Wang Y, Bowman JM, Kamarchik E. Five ab initio potential energy and dipole moment surfaces for hydrated NaCl and NaF. I. Two-body interactions. J Chem Phys 2016; 144:114311. [DOI: 10.1063/1.4943580] [Citation(s) in RCA: 11] [Impact Index Per Article: 1.4] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/14/2022] Open
Affiliation(s)
- Yimin Wang
- Department of Chemistry, Cherry L. Emerson Center for Scientific Computation, Emory University, Atlanta, Georgia 30322, USA
| | - Joel M. Bowman
- Department of Chemistry, Cherry L. Emerson Center for Scientific Computation, Emory University, Atlanta, Georgia 30322, USA
| | - Eugene Kamarchik
- Quantum Pomegranate, LLC, 2604 Kings Lake Court NE, Atlanta, Georgia 30345, USA
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34
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Samanta AK, Wang Y, Mancini JS, Bowman JM, Reisler H. Energetics and Predissociation Dynamics of Small Water, HCl, and Mixed HCl–Water Clusters. Chem Rev 2016; 116:4913-36. [DOI: 10.1021/acs.chemrev.5b00506] [Citation(s) in RCA: 41] [Impact Index Per Article: 5.1] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/28/2022]
Affiliation(s)
- Amit K. Samanta
- Department
of Chemistry, University of Southern California, Los Angeles, California 90089-0482, United States
| | - Yimin Wang
- Department
of Chemistry and Cherry L. Emerson Center for Scientific Computation, Emory University, Atlanta, Georgia 30322, United States
| | - John S. Mancini
- Department
of Chemistry and Cherry L. Emerson Center for Scientific Computation, Emory University, Atlanta, Georgia 30322, United States
| | - Joel M. Bowman
- Department
of Chemistry and Cherry L. Emerson Center for Scientific Computation, Emory University, Atlanta, Georgia 30322, United States
| | - Hanna Reisler
- Department
of Chemistry, University of Southern California, Los Angeles, California 90089-0482, United States
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