1
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Dwivedi A, Lopez-Ruiz MA, Iyengar SS. Resource Optimization for Quantum Dynamics with Tensor Networks: Quantum and Classical Algorithms. J Phys Chem A 2024; 128:6774-6797. [PMID: 39101545 DOI: 10.1021/acs.jpca.4c03407] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 08/06/2024]
Abstract
The exponential scaling of the quantum degrees of freedom with the size of the system is one of the biggest challenges in computational chemistry and particularly in quantum dynamics. We present a tensor network approach for the time-evolution of the nuclear degrees of freedom of multiconfigurational chemical systems at a reduced storage and computational complexity. We also present quantum algorithms for the resultant dynamics. To preserve the compression advantage achieved via tensor network decompositions, we present an adaptive algorithm for the regularization of nonphysical bond dimensions, preventing the potentially exponential growth of these with time. While applicable to any quantum dynamical problem, our method is particularly valuable for dynamical simulations of nuclear chemical systems. Our algorithm is demonstrated using ab initio potentials obtained for a symmetric hydrogen-bonded system, namely, the protonated 2,2'-bipyridine, and compared to exact diagonalization numerical results.
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Affiliation(s)
- Anurag Dwivedi
- Department of Chemistry, Indiana University, Bloomington, Indiana 47405, United States
- Indiana University Quantum Science and Engineering Center (IU-QSEC), Indiana University, Bloomington, Indiana 47405, United States
| | - Miguel Angel Lopez-Ruiz
- Department of Chemistry, Indiana University, Bloomington, Indiana 47405, United States
- Indiana University Quantum Science and Engineering Center (IU-QSEC), Indiana University, Bloomington, Indiana 47405, United States
| | - Srinivasan S Iyengar
- Department of Chemistry, Indiana University, Bloomington, Indiana 47405, United States
- Indiana University Quantum Science and Engineering Center (IU-QSEC), Indiana University, Bloomington, Indiana 47405, United States
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2
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van Tetering L, Spies S, Wildeman QDK, Houthuijs KJ, van Outersterp RE, Martens J, Wevers RA, Wishart DS, Berden G, Oomens J. A spectroscopic test suggests that fragment ion structure annotations in MS/MS libraries are frequently incorrect. Commun Chem 2024; 7:30. [PMID: 38355930 PMCID: PMC10867025 DOI: 10.1038/s42004-024-01112-7] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/18/2023] [Accepted: 01/22/2024] [Indexed: 02/16/2024] Open
Abstract
Modern untargeted mass spectrometry (MS) analyses quickly detect and resolve thousands of molecular compounds. Although features are readily annotated with a molecular formula in high-resolution small-molecule MS applications, the large majority of them remains unidentified in terms of their full molecular structure. Collision-induced dissociation tandem mass spectrometry (CID-MS2) provides a diagnostic molecular fingerprint to resolve the molecular structure through a library search. However, for de novo identifications, one must often rely on in silico generated MS2 spectra as reference. The ability of different in silico algorithms to correctly predict MS2 spectra and thus to retrieve correct molecular structures is a topic of lively debate, for instance in the CASMI contest. Underlying the predicted MS2 spectra are the in silico generated product ion structures, which are normally not used in de novo identification, but which can serve to critically assess the fragmentation algorithms. Here we evaluate in silico generated MSn product ion structures by comparison with structures established experimentally by infrared ion spectroscopy (IRIS). For a set of three dozen product ion structures from five precursor molecules, we find that virtually all fragment ion structure annotations in three major in silico MS2 libraries (HMDB, METLIN, mzCloud) are incorrect and caution the reader against their use for structure annotation of MS/MS ions.
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Affiliation(s)
- Lara van Tetering
- Radboud University, Institute for Molecules and Materials, FELIX Laboratory, Toernooiveld 7, 6525ED, Nijmegen, The Netherlands
| | - Sylvia Spies
- Radboud University, Institute for Molecules and Materials, FELIX Laboratory, Toernooiveld 7, 6525ED, Nijmegen, The Netherlands
| | - Quirine D K Wildeman
- Radboud University, Institute for Molecules and Materials, FELIX Laboratory, Toernooiveld 7, 6525ED, Nijmegen, The Netherlands
| | - Kas J Houthuijs
- Radboud University, Institute for Molecules and Materials, FELIX Laboratory, Toernooiveld 7, 6525ED, Nijmegen, The Netherlands
| | - Rianne E van Outersterp
- Radboud University, Institute for Molecules and Materials, FELIX Laboratory, Toernooiveld 7, 6525ED, Nijmegen, The Netherlands
| | - Jonathan Martens
- Radboud University, Institute for Molecules and Materials, FELIX Laboratory, Toernooiveld 7, 6525ED, Nijmegen, The Netherlands
| | - Ron A Wevers
- Department of Laboratory Medicine, Translational Metabolic Laboratory, Radboud University Medical Center, Geert Grooteplein Zuid 10, 6525GA, Nijmegen, The Netherlands
| | - David S Wishart
- Departments of Computing Science and Biological Sciences, University of Alberta, Edmonton, AB, Canada
| | - Giel Berden
- Radboud University, Institute for Molecules and Materials, FELIX Laboratory, Toernooiveld 7, 6525ED, Nijmegen, The Netherlands
| | - Jos Oomens
- Radboud University, Institute for Molecules and Materials, FELIX Laboratory, Toernooiveld 7, 6525ED, Nijmegen, The Netherlands.
- van 't Hoff Institute for Molecular Sciences, University of Amsterdam, Science Park 904, 1098XH, Amsterdam, The Netherlands.
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3
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Martínez-Haya B, Avilés-Moreno JR, Gámez F, Martens J, Oomens J, Berden G. Correlated proton dynamics in hydrogen bonding networks: the benchmark case of 3-hydroxyglutaric acid. Phys Chem Chem Phys 2023; 26:198-208. [PMID: 38053486 DOI: 10.1039/d3cp04514e] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/07/2023]
Abstract
Proton and hydrogen-bonded networks sustain a broad range of structural and charge transfer processes in supramolecular materials. The modelling of proton dynamics is however challenging and demands insights from prototypical benchmark systems. The intramolecular H-bonding networks induced by either protonation or deprotonation of 3-hydroxyglutaric acid provide intriguing case studies of correlated proton dynamics. The vibrational signatures associated with the fluxional proton bonding and its coupling with the hydroxyglutaric backbone are investigated here with infrared action ion spectroscopy experiments and Born-Oppenheimer molecular dynamics (BOMD) computations. Despite the formally similar symmetry of protonated and deprotonated hydroxyglutaric acid, the relative proton affinities of the oxygen centers of the carboxylic and carboxylate groups with respect to that of the central hydroxyl group lead to distinct proton dynamics. In the protonated acid, a tautomeric arrangement of the type HOCO·[HOH]+·OCOH is preferred with the proton binding tighter to the central hydroxyl moiety and the electronic density being shared between the two nearly symmetric H-bonds with the carboxylic end groups. In the deprotonated acid, the asymmetric [OCO]-·HO·HOCO configuration is more stable, with a stronger H-bonding on the bare carboxylate end. Both systems display active backbone dynamics and concerted Grothuss-like proton motions, leading to diffuse band structures in their vibrational spectra. These features are accurately reproduced by the BOMD computations.
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Affiliation(s)
- Bruno Martínez-Haya
- Center for Nanoscience and Sustainable Technologies (CNATS), Universidad Pablo de Olavide, E-41013 Seville, Spain.
| | - Juan Ramón Avilés-Moreno
- Department of Applied Physical Chemistry, Universidad Autónoma de Madrid, E-28049, Madrid, Spain
| | - Francisco Gámez
- Departamento de Química Física, Universidad Complutense, E-28040 Madrid, Spain
| | - Jonathan Martens
- Institute for Molecules and Materials, FELIX Laboratory, Radboud University, Toernooiveld 7, 6525ED Nijmegen, The Netherlands
| | - Jos Oomens
- Institute for Molecules and Materials, FELIX Laboratory, Radboud University, Toernooiveld 7, 6525ED Nijmegen, The Netherlands
| | - Giel Berden
- Institute for Molecules and Materials, FELIX Laboratory, Radboud University, Toernooiveld 7, 6525ED Nijmegen, The Netherlands
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4
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Martínez-Haya B, Avilés-Moreno JR, Gámez F, Martens J, Oomens J, Berden G. A Dynamic Proton Bond: MH +·H 2O ⇌ M·H 3O + Interconversion in Loosely Coordinated Environments. J Phys Chem Lett 2023; 14:1294-1300. [PMID: 36723385 PMCID: PMC9923742 DOI: 10.1021/acs.jpclett.2c03832] [Citation(s) in RCA: 4] [Impact Index Per Article: 4.0] [Reference Citation Analysis] [Abstract] [Grants] [Track Full Text] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/18/2022] [Accepted: 01/26/2023] [Indexed: 06/18/2023]
Abstract
The interaction of organic molecules with oxonium cations within their solvation shell may lead to the emergence of dynamic supramolecular structures with recurrently changing host-guest chemical identity. We illustrate this phenomenon in benchmark proton-bonded complexes of water with polyether macrocyles. Despite the smaller proton affinity of water versus the ether group, water in fact retains the proton in the form of H3O+, with increasing stability as the coordination number increases. Hindrance in many-fold coordination induces dynamic reversible (ether)·H3O+ ⇌ (etherH+)·H2O interconversion. We perform infrared action ion spectroscopy over a broad spectral range to expose the vibrational signatures of the loose proton bonding in these systems. Remarkably, characteristic bands for the two limiting proton bonding configurations are observed in the experimental vibrational spectra, superimposed onto diffuse bands associated with proton delocalization. These features cannot be described by static equilibrium structures but are accurately modeled within the framework of ab initio molecular dynamics.
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Affiliation(s)
- Bruno Martínez-Haya
- Department
of Physical, Chemical and Natural Systems, Universidad Pablo de Olavide, 41013 Seville, Spain
| | | | - Francisco Gámez
- Departamento
de Química Física, Universidad Complutense, 28040 Madrid, Spain
| | - Jonathan Martens
- Institute
for Molecules and Materials, FELIX Laboratory, Radboud University, Toernooiveld 7, 6525ED Nijmegen, The Netherlands
| | - Jos Oomens
- Institute
for Molecules and Materials, FELIX Laboratory, Radboud University, Toernooiveld 7, 6525ED Nijmegen, The Netherlands
| | - Giel Berden
- Institute
for Molecules and Materials, FELIX Laboratory, Radboud University, Toernooiveld 7, 6525ED Nijmegen, The Netherlands
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5
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Zhu X, Iyengar SS. Graph Theoretic Molecular Fragmentation for Multidimensional Potential Energy Surfaces Yield an Adaptive and General Transfer Machine Learning Protocol. J Chem Theory Comput 2022; 18:5125-5144. [PMID: 35994592 DOI: 10.1021/acs.jctc.1c01241] [Citation(s) in RCA: 5] [Impact Index Per Article: 2.5] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/19/2022]
Abstract
Over a series of publications we have introduced a graph-theoretic description for molecular fragmentation. Here, a system is divided into a set of nodes, or vertices, that are then connected through edges, faces, and higher-order simplexes to represent a collection of spatially overlapping and locally interacting subsystems. Each such subsystem is treated at two levels of electronic structure theory, and the result is used to construct many-body expansions that are then embedded within an ONIOM-scheme. These expansions converge rapidly with many-body order (or graphical rank) of subsystems and have been previously used for ab initio molecular dynamics (AIMD) calculations and for computing multidimensional potential energy surfaces. Specifically, in all these cases we have shown that CCSD and MP2 level AIMD trajectories and potential surfaces may be obtained at density functional theory cost. The approach has been demonstrated for gas-phase studies, for condensed phase electronic structure, and also for basis set extrapolation-based AIMD. Recently, this approach has also been used to derive new quantum-computing algorithms that enormously reduce the quantum circuit depth in a circuit-based computation of correlated electronic structure. In this publication, we introduce (a) a family of neural networks that act in parallel to represent, efficiently, the post-Hartree-Fock electronic structure energy contributions for all simplexes (fragments), and (b) a new k-means-based tessellation strategy to glean training data for high-dimensional molecular spaces and minimize the extent of training needed to construct this family of neural networks. The approach is particularly useful when coupled cluster accuracy is desired and when fragment sizes grow in order to capture nonlocal interactions accurately. The unique multidimensional k-means tessellation/clustering algorithm used to determine our training data for all fragments is shown to be extremely efficient and reduces the needed training to only 10% of data for all fragments to obtain accurate neural networks for each fragment. These fully connected dense neural networks are then used to extrapolate the potential energy surface for all molecular fragments, and these are then combined as per our graph-theoretic procedure to transfer the learning process to a full system energy for the entire AIMD trajectory at less than one-tenth the cost as compared to a regular fragmentation-based AIMD calculation.
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Affiliation(s)
- Xiao Zhu
- Department of Chemistry and Department of Physics, Indiana University, 800 E. Kirkwood Avenue, Bloomington 47405, Indiana, United States
| | - Srinivasan S Iyengar
- Department of Chemistry and Department of Physics, Indiana University, 800 E. Kirkwood Avenue, Bloomington 47405, Indiana, United States
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6
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Saha D, Iyengar SS, Richerme P, Smith JM, Sabry A. Mapping Quantum Chemical Dynamics Problems to Spin-Lattice Simulators. J Chem Theory Comput 2021; 17:6713-6732. [PMID: 34694820 DOI: 10.1021/acs.jctc.1c00688] [Citation(s) in RCA: 3] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/28/2022]
Abstract
The accurate computational determination of chemical, materials, biological, and atmospheric properties has a critical impact on a wide range of health and environmental problems, but is deeply limited by the computational scaling of quantum mechanical methods. The complexity of quantum chemical studies arises from the steep algebraic scaling of electron correlation methods and the exponential scaling in studying nuclear dynamics and molecular flexibility. To date, efforts to apply quantum hardware to such quantum chemistry problems have focused primarily on electron correlation. Here, we provide a framework that allows for the solution of quantum chemical nuclear dynamics by mapping these to quantum spin-lattice simulators. Using the example case of a short-strong hydrogen-bonded system, we construct the Hamiltonian for the nuclear degrees of freedom on a single Born-Oppenheimer surface and show how it can be transformed to a generalized Ising model Hamiltonian. We then demonstrate a method to determine the local fields and spin-spin couplings needed to identically match the molecular and spin-lattice Hamiltonians. We describe a protocol to determine the on-site and intersite coupling parameters of this Ising Hamiltonian from the Born-Oppenheimer potential and nuclear kinetic energy operator. Our approach represents a paradigm shift in the methods used to study quantum nuclear dynamics, opening the possibility to solve both electronic structure and nuclear dynamics problems using quantum computing systems.
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Affiliation(s)
- Debadrita Saha
- Department of Chemistry, and the Indiana University Quantum Science and Engineering Center (IU-QSEC), Indiana University, Bloomington, Indiana 47405, United States
| | - Srinivasan S Iyengar
- Department of Chemistry, and the Indiana University Quantum Science and Engineering Center (IU-QSEC), Indiana University, Bloomington, Indiana 47405, United States
| | - Philip Richerme
- Department of Physics and the Indiana University Quantum Science and Engineering Center (IU-QSEC), Indiana University, Bloomington, Indiana 47405, United States
| | - Jeremy M Smith
- Department of Chemistry, Indiana University, 800 E. Kirkwood Avenue, Bloomington, Indiana 47405, United States
| | - Amr Sabry
- Department of Computer Science, School of Informatics, Computing, and Engineering, and the Indiana University Quantum Science and Engineering Center (IU-QSEC), Indiana University, Bloomington, Indiana 47405, United States
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7
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Gámez F, Avilés-Moreno JR, Berden G, Oomens J, Martínez-Haya B. Proton in the ring: spectroscopy and dynamics of proton bonding in macrocycle cavities. Phys Chem Chem Phys 2021; 23:21532-21543. [PMID: 34549205 DOI: 10.1039/d1cp03033g] [Citation(s) in RCA: 4] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/21/2022]
Abstract
The proton bond is a paradigmatic quantum molecular interaction and a major driving force of supramolecular chemistry. The ring cavities of crown ethers provide an intriguing environment, promoting competitive proton sharing with multiple coordination anchors. This study shows that protons confined in crown ether cavities form dynamic bonds that migrate to varying pairs of coordinating atoms when allowed by the flexibility of the macrocycle backbone. Prototypic native crown ethers (12-crown-4, 15-crown-5 and 18-crown-6) and aza-crown ethers (cyclen, 1-aza-18-crown-6 and hexacyclen) are investigated. For each system, Infrared action spectroscopy experiments and ab initio Molecular Dynamics computations are employed to elucidate the structural effects associated with proton diffusion and its entanglement with the conformational and vibrational dynamics of the protonated host.
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Affiliation(s)
- Francisco Gámez
- Department of Physical Chemistry, Universidad de Granada, Avenida de la Fuente Nueva s/n, 18071, Granada, Spain
| | - Juan R Avilés-Moreno
- Department of Applied Physical Chemistry, Universidad Autónoma de Madrid, 28049, Madrid, Spain
| | - Giel Berden
- FELIX Laboratory, Institute for Molecules and Materials, Radboud University, Toernooiveld 7, 6525ED Nijmegen, The Netherlands
| | - Jos Oomens
- FELIX Laboratory, Institute for Molecules and Materials, Radboud University, Toernooiveld 7, 6525ED Nijmegen, The Netherlands
| | - Bruno Martínez-Haya
- Department of Physical, Chemical and Natural Systems, Universidad Pablo de Olavide, Ctra. de Utrera, km. 1, 41013 Seville, Spain.
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8
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Zhang JH, Ricard TC, Haycraft C, Iyengar SS. Weighted-Graph-Theoretic Methods for Many-Body Corrections within ONIOM: Smooth AIMD and the Role of High-Order Many-Body Terms. J Chem Theory Comput 2021; 17:2672-2690. [PMID: 33891416 DOI: 10.1021/acs.jctc.0c01287] [Citation(s) in RCA: 10] [Impact Index Per Article: 3.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/27/2022]
Abstract
We present a weighted-graph-theoretic approach to adaptively compute contributions from many-body approximations for smooth and accurate post-Hartree-Fock (pHF) ab initio molecular dynamics (AIMD) of highly fluxional chemical systems. This approach is ONIOM-like, where the full system is treated at a computationally feasible quality of treatment (density functional theory (DFT) for the size of systems considered in this publication), which is then improved through a perturbative correction that captures local many-body interactions up to a certain order within a higher level of theory (post-Hartree-Fock in this publication) described through graph-theoretic techniques. Due to the fluxional and dynamical nature of the systems studied here, these graphical representations evolve during dynamics. As a result, energetic "hops" appear as the graphical representation deforms with the evolution of the chemical and physical properties of the system. In this paper, we introduce dynamically weighted, linear combinations of graphs, where the transition between graphical representations is smoothly achieved by considering a range of neighboring graphical representations at a given instant during dynamics. We compare these trajectories with those obtained from a set of trajectories where the range of local many-body interactions considered is increased, sometimes to the maximum available limit, which yields conservative trajectories as the order of interactions is increased. The weighted-graph approach presents improved dynamics trajectories while only using lower-order many-body interaction terms. The methods are compared by computing dynamical properties through time-correlation functions and structural distribution functions. In all cases, the weighted-graph approach provides accurate results at a lower cost.
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Affiliation(s)
- Juncheng Harry Zhang
- Department of Chemistry and Department of Physics, Indiana University, 800 East Kirkwood Avenue, Bloomington, Indiana 47405, United States
| | - Timothy C Ricard
- Department of Chemistry and Department of Physics, Indiana University, 800 East Kirkwood Avenue, Bloomington, Indiana 47405, United States
| | - Cody Haycraft
- Department of Chemistry and Department of Physics, Indiana University, 800 East Kirkwood Avenue, Bloomington, Indiana 47405, United States
| | - Srinivasan S Iyengar
- Department of Chemistry and Department of Physics, Indiana University, 800 East Kirkwood Avenue, Bloomington, Indiana 47405, United States
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9
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Kumar A, Iyengar SS. Fragment-Based Electronic Structure for Potential Energy Surfaces Using a Superposition of Fragmentation Topologies. J Chem Theory Comput 2019; 15:5769-5786. [DOI: 10.1021/acs.jctc.9b00608] [Citation(s) in RCA: 9] [Impact Index Per Article: 1.8] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/25/2022]
Affiliation(s)
- Anup Kumar
- Department of Chemistry and Department of Physics, Indiana University, 800 East Kirkwood Avenue, Bloomington, Indiana-47405, United States
| | - Srinivasan S. Iyengar
- Department of Chemistry and Department of Physics, Indiana University, 800 East Kirkwood Avenue, Bloomington, Indiana-47405, United States
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10
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Tan JA, Kuo JL. A theoretical study on the infrared signatures of proton-bound rare gas dimers (Rg-H +-Rg), Rg = {Ne, Ar, Kr, and Xe}. J Chem Phys 2019; 150:124305. [PMID: 30927880 DOI: 10.1063/1.5090031] [Citation(s) in RCA: 16] [Impact Index Per Article: 3.2] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/14/2022] Open
Abstract
The infrared spectrum of proton-bound rare gas dimers has been extensively studied via matrix isolation spectroscopy. However, little attention has been paid on their spectrum in the gas phase. Most of the Rg2H+ has not been detected outside the matrix environment. Recently, ArnH+ (n = 3-7) has been first detected in the gas-phase [D. C. McDonald et al., J. Chem. Phys. 145, 231101 (2016)]. In that work, anharmonic theory can reproduce the observed vibrational structure. In this paper, we extend the existing theory to examine the vibrational signatures of Rg2H+, Rg = {Ne, Ar, Kr, and Xe}. The successive binding of Rg to H+ was investigated through the calculation of stepwise formation energies. It was found that this binding is anti-cooperative. High-level full-dimensional potential energy surfaces at the CCSD(T)/aug-cc-pVQZ//MP2/aug-cc-pVQZ were constructed and used in the anharmonic calculation via discrete variable representation. We found that the potential coupling between the symmetric and asymmetric Rg-H+ stretch (ν1 and ν3 respectively) causes a series of bright n1ν1 + ν3 progressions. From Ne2H+ to Xe2H+, an enhancement of intensities for these bands was observed.
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Affiliation(s)
- Jake A Tan
- Institute of Atomic and Molecular Sciences, Academia Sinica, No. 1 Roosevelt Road, Section 4, Taipei 10617, Taiwan
| | - Jer-Lai Kuo
- Institute of Atomic and Molecular Sciences, Academia Sinica, No. 1 Roosevelt Road, Section 4, Taipei 10617, Taiwan
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11
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Ricard TC, Iyengar SS. Efficiently Capturing Weak Interactions in ab Initio Molecular Dynamics with on-the-Fly Basis Set Extrapolation. J Chem Theory Comput 2018; 14:5535-5552. [DOI: 10.1021/acs.jctc.8b00803] [Citation(s) in RCA: 11] [Impact Index Per Article: 1.8] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/28/2022]
Affiliation(s)
- Timothy C. Ricard
- Department of Chemistry and Department of Physics, Indiana University, 800 E. Kirkwood Avenue, Bloomington, Indiana 47405, United States
| | - Srinivasan S. Iyengar
- Department of Chemistry and Department of Physics, Indiana University, 800 E. Kirkwood Avenue, Bloomington, Indiana 47405, United States
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12
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Inakollu VSS, Yu H. A systematic benchmarking of computational vibrational spectroscopy with DFTB3: Normal mode analysis and fast Fourier transform dipole autocorrelation function. J Comput Chem 2018; 39:2067-2078. [DOI: 10.1002/jcc.25390] [Citation(s) in RCA: 5] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/08/2018] [Revised: 06/04/2018] [Accepted: 06/12/2018] [Indexed: 11/10/2022]
Affiliation(s)
- V. S. Sandeep Inakollu
- School of Chemistry and Molecular Bioscience University of Wollongong Wollongong New South Wales 2522 Australia
- Molecular Horizons University of Wollongong New South Wales 2522 Australia
| | - Haibo Yu
- School of Chemistry and Molecular Bioscience University of Wollongong Wollongong New South Wales 2522 Australia
- Molecular Horizons University of Wollongong New South Wales 2522 Australia
- Illawarra Health and Medical Research Institute Wollongong New South Wales 2522 Australia
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13
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Ricard TC, Haycraft C, Iyengar SS. Adaptive, Geometric Networks for Efficient Coarse-Grained Ab Initio Molecular Dynamics with Post-Hartree–Fock Accuracy. J Chem Theory Comput 2018; 14:2852-2866. [DOI: 10.1021/acs.jctc.8b00186] [Citation(s) in RCA: 13] [Impact Index Per Article: 2.2] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/24/2022]
Affiliation(s)
- Timothy C. Ricard
- Department of Chemistry and Department of Physics, Indiana University, 800 East Kirkwood Avenue, Bloomington, Indiana 47405, United States
| | - Cody Haycraft
- Department of Chemistry and Department of Physics, Indiana University, 800 East Kirkwood Avenue, Bloomington, Indiana 47405, United States
| | - Srinivasan S. Iyengar
- Department of Chemistry and Department of Physics, Indiana University, 800 East Kirkwood Avenue, Bloomington, Indiana 47405, United States
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14
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Avilés-Moreno JR, Berden G, Oomens J, Martínez-Haya B. Intra-cavity proton bonding and anharmonicity in the anionophore cyclen. Phys Chem Chem Phys 2018; 20:8968-8975. [PMID: 29557457 DOI: 10.1039/c8cp00660a] [Citation(s) in RCA: 6] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/16/2023]
Abstract
Proton bonding drives the supramolecular chemistry of a broad range of materials with polar moieties. Proton delocalization and electronic charge redistribution have a profound impact on the structure of proton-bound molecular frameworks, and pose fundamental challenges to quantum chemical modelling. This study provides insights into the structural and spectral signatures of the intramolecular proton bond formed in a benchmark polyazamacrocycle anionophore (cyclen, 1,4,7,10-tetraazacyclododecane). Infrared action spectroscopy is employed to characterize the macrocycle, isolated in protonated form. In its most stable configuration, protonated cyclen adopts an open arrangement of Cs symmetry with a particularly strong NHδ+N bond across the cavity. The quantum chemical analysis of the infrared spectrum reveals intrinsic difficulties for the accurate description of the vibrational modes of the system. The reconciliation of the computational predictions with experiment demands a careful anharmonic treatment of the proton motion, which exposes the limitations of current methods. Best results are obtained with the incorporation of anharmonicity only to the fundamental modes directly related to motions of the proton. However, the full anharmonic treatment of the system fails to describe correctly the vibrations related to the macrocycle backbone. The results should serve as motivation for new developments in the modelling of proton bonded systems.
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Affiliation(s)
- Juan Ramón Avilés-Moreno
- Department of Physical, Chemical and Natural Systems, Universidad Pablo de Olavide, E-41013 Seville, Spain.
| | - Giel Berden
- Radboud University, Institute for Molecules and Materials, FELIX Laboratory, Toernooiveld 7c, 6525ED Nijmegen, The Netherlands
| | - Jos Oomens
- Radboud University, Institute for Molecules and Materials, FELIX Laboratory, Toernooiveld 7c, 6525ED Nijmegen, The Netherlands
| | - Bruno Martínez-Haya
- Department of Physical, Chemical and Natural Systems, Universidad Pablo de Olavide, E-41013 Seville, Spain.
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15
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DeGregorio N, Iyengar SS. Efficient and Adaptive Methods for Computing Accurate Potential Surfaces for Quantum Nuclear Effects: Applications to Hydrogen-Transfer Reactions. J Chem Theory Comput 2017; 14:30-47. [DOI: 10.1021/acs.jctc.7b00927] [Citation(s) in RCA: 12] [Impact Index Per Article: 1.7] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/27/2022]
Affiliation(s)
- Nicole DeGregorio
- Department of Chemistry and
Department of Physics, Indiana University, 800 E. Kirkwood Avenue, Bloomington, Indiana 47405, United States
| | - Srinivasan S. Iyengar
- Department of Chemistry and
Department of Physics, Indiana University, 800 E. Kirkwood Avenue, Bloomington, Indiana 47405, United States
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16
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Haycraft C, Li J, Iyengar SS. Efficient, “On-the-Fly”, Born–Oppenheimer and Car–Parrinello-type Dynamics with Coupled Cluster Accuracy through Fragment Based Electronic Structure. J Chem Theory Comput 2017; 13:1887-1901. [DOI: 10.1021/acs.jctc.6b01107] [Citation(s) in RCA: 18] [Impact Index Per Article: 2.6] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/06/2023]
Affiliation(s)
- Cody Haycraft
- Department of Chemistry and
Department of Physics, Indiana University, 800 East Kirkwood Avenue, Bloomington, Indiana 47405, United States
| | - Junjie Li
- Department of Chemistry and
Department of Physics, Indiana University, 800 East Kirkwood Avenue, Bloomington, Indiana 47405, United States
| | - Srinivasan S. Iyengar
- Department of Chemistry and
Department of Physics, Indiana University, 800 East Kirkwood Avenue, Bloomington, Indiana 47405, United States
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17
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Takahashi M, Okamura N, Fan X, Shirakawa H, Minamide H. Temperature Dependence in the Terahertz Spectrum of Nicotinamide: Anharmonicity and Hydrogen-Bonded Network. J Phys Chem A 2017; 121:2558-2564. [DOI: 10.1021/acs.jpca.6b11049] [Citation(s) in RCA: 18] [Impact Index Per Article: 2.6] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/29/2022]
Affiliation(s)
- Masae Takahashi
- Graduate
School of Agricultural Science, Tohoku University, Sendai 980-0845, Japan
- RIKEN Advanced Science Institute, Sendai 980-0845, Japan
| | - Nubuyuki Okamura
- Graduate
School of Agricultural Science, Tohoku University, Sendai 980-0845, Japan
- RIKEN Advanced Science Institute, Sendai 980-0845, Japan
| | - Xinyi Fan
- Graduate
School of Agricultural Science, Tohoku University, Sendai 980-0845, Japan
| | - Hitoshi Shirakawa
- Graduate
School of Agricultural Science, Tohoku University, Sendai 980-0845, Japan
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18
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Sager LM, Iyengar SS. Proton relays in anomalous carbocations dictate spectroscopy, stability, and mechanisms: case studies on C2H5+ and C3H3+. Phys Chem Chem Phys 2017; 19:27801-27816. [DOI: 10.1039/c7cp05577c] [Citation(s) in RCA: 5] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/21/2022]
Abstract
We present a detailed exposition of “Grothuss-like” proton shuttles in C2H5+ and C3H3+ that result in anomalous structural and spectral behavior.
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Affiliation(s)
- LeeAnn M. Sager
- Department of Chemistry and Department of Physics
- Indiana University
- Bloomington
- USA
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19
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Li J, Haycraft C, Iyengar SS. Hybrid Extended Lagrangian, Post-Hartree–Fock Born–Oppenheimer ab Initio Molecular Dynamics Using Fragment-Based Electronic Structure. J Chem Theory Comput 2016; 12:2493-508. [DOI: 10.1021/acs.jctc.6b00001] [Citation(s) in RCA: 27] [Impact Index Per Article: 3.4] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/28/2022]
Affiliation(s)
- Junjie Li
- Department of Chemistry and
Department of Physics, Indiana University, 800 E. Kirkwood Ave., Bloomington, Indiana 47405, United States
| | - Cody Haycraft
- Department of Chemistry and
Department of Physics, Indiana University, 800 E. Kirkwood Ave., Bloomington, Indiana 47405, United States
| | - Srinivasan S. Iyengar
- Department of Chemistry and
Department of Physics, Indiana University, 800 E. Kirkwood Ave., Bloomington, Indiana 47405, United States
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20
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Li J, Pacheco AB, Raghavachari K, Iyengar SS. A Grotthuss-like proton shuttle in the anomalous C2H3+ carbocation: energetic and vibrational properties for isotopologues. Phys Chem Chem Phys 2016; 18:29395-29411. [DOI: 10.1039/c6cp04450f] [Citation(s) in RCA: 10] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/21/2022]
Abstract
The proton shuttle in C2H3+ is reminiscent of the Grotthuss proton transfer mechanism.
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Affiliation(s)
- Junjie Li
- Department of Chemistry and Department of Physics
- Indiana University
- Bloomington
- USA
| | - Alexander B. Pacheco
- Department of Chemistry and Department of Physics
- Indiana University
- Bloomington
- USA
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21
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Tan JA, Kuo JL. Strong Quantum Coupling in the Vibrational Signatures of a Symmetric Ionic Hydrogen Bond: The Case of (CH3OH)2H+. J Phys Chem A 2015; 119:11320-8. [DOI: 10.1021/acs.jpca.5b10554] [Citation(s) in RCA: 16] [Impact Index Per Article: 1.8] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/29/2022]
Affiliation(s)
- Jake A. Tan
- Molecular
Science and Technology Program, Taiwan International Graduate Program, Academia Sinica, 128 Academia Road, Section 2, Nangang, Taipei 115, Taiwan, ROC
- Department
of Chemistry, National Tsing Hua University, 101 Kuang-Fu Road, Section 2, Hsinchu 30013, Taiwan, ROC
- Institute
of Atomic and Molecular Sciences, Academia Sinica, No.1 Roosevelt
Road, Section 4, Taipei 10617, Taiwan, ROC
| | - Jer-Lai Kuo
- Molecular
Science and Technology Program, Taiwan International Graduate Program, Academia Sinica, 128 Academia Road, Section 2, Nangang, Taipei 115, Taiwan, ROC
- Institute
of Atomic and Molecular Sciences, Academia Sinica, No.1 Roosevelt
Road, Section 4, Taipei 10617, Taiwan, ROC
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22
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Li J, Iyengar SS. Ab Initio Molecular Dynamics Using Recursive, Spatially Separated, Overlapping Model Subsystems Mixed within an ONIOM-Based Fragmentation Energy Extrapolation Technique. J Chem Theory Comput 2015; 11:3978-91. [DOI: 10.1021/acs.jctc.5b00433] [Citation(s) in RCA: 21] [Impact Index Per Article: 2.3] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/30/2022]
Affiliation(s)
- Junjie Li
- Department of Chemistry and
Department of Physics, Indiana University, 800 E. Kirkwood Ave, Bloomington, Indiana 47405, United States
| | - Srinivasan S. Iyengar
- Department of Chemistry and
Department of Physics, Indiana University, 800 E. Kirkwood Ave, Bloomington, Indiana 47405, United States
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23
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Phatak P, Venderley J, Debrota J, Li J, Iyengar SS. Active Site Dynamical Effects in the Hydrogen Transfer Rate-limiting Step in the Catalysis of Linoleic Acid by Soybean Lipoxygenase-1 (SLO-1): Primary and Secondary Isotope Contributions. J Phys Chem B 2015; 119:9532-46. [PMID: 26079999 DOI: 10.1021/acs.jpcb.5b02385] [Citation(s) in RCA: 15] [Impact Index Per Article: 1.7] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/28/2022]
Abstract
Using ab initio molecular dynamics (AIMD) simulations that facilitate the treatment of rare events, we probe the active site participation in the rate-determining hydrogen transfer step in the catalytic oxidation of linoleic acid by soybean lipoxygenase-1 (SLO-1). The role of two different active site components is probed. (a) On the hydrogen atom acceptor side of the active site, the hydrogen bonding propensity between the acceptor side hydroxyl group, which is bound to the iron cofactor, and the backbone carboxyl group of isoleucine (residue number 839) is studied toward its role in promoting the hydrogen transfer event. Primary and secondary (H/D) isotope effects are also probed and a definite correlation with subtle secondary H/D isotope effects is found. With increasing average nuclear kinetic energy, the increase in transfer probability is enhanced due to the presence of the hydrogen bond between the backbone carbonyl of I839 and the acceptor oxygen. Further increase in average nuclear kinetic energy reduces the strength of this secondary hydrogen bond which leads to a deterioration in hydrogen transfer rates and finally embrances an Arrhenius-like behavior. (b) On the hydrogen atom donor side, the coupling between vibrational modes predominantly localized on the donor-side linoleic acid group and the reactive mode is probed. There appears to be a qualitative difference in the coupling between modes that belong to linoleic acid and the hydrogen transfer mode, for hydrogen and deuterium transfer. For example, the donor side secondary hydrogen atom is much more labile (by nearly a factor of 5) during deuterium transfer as compared to the case for hydrogen transfer. This appears to indicate a greater coupling between the modes belonging to the linoleic acid scaffold and the deuterium transfer mode and also provides a new rationalization for the abnormal (nonclassical) secondary isotope effect results obtained by Knapp, Rickert, and Klinman in J. Am. Chem. Soc. , 2002 , 124 , 3865 . To substantiate our findings noted in point a above, we have suggested an I839 → A839 or I839 → V839 mutation. This will modify the bulkiness of hydrogen the bonding residue, allowing greater flexibility in the secondary hydrogen bond formation highlighted above and adversely affecting the reaction rate.
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Affiliation(s)
- Prasad Phatak
- Department of Chemistry and Department of Physics, Indiana University, 800 East Kirkwood Avenue, Bloomington, Indiana 47405, United States
| | - Jordan Venderley
- Department of Chemistry and Department of Physics, Indiana University, 800 East Kirkwood Avenue, Bloomington, Indiana 47405, United States
| | - John Debrota
- Department of Chemistry and Department of Physics, Indiana University, 800 East Kirkwood Avenue, Bloomington, Indiana 47405, United States
| | - Junjie Li
- Department of Chemistry and Department of Physics, Indiana University, 800 East Kirkwood Avenue, Bloomington, Indiana 47405, United States
| | - Srinivasan S Iyengar
- Department of Chemistry and Department of Physics, Indiana University, 800 East Kirkwood Avenue, Bloomington, Indiana 47405, United States
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24
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Ung HU, Moehlig AR, Kudla RA, Mueller LJ, Oomens J, Berden G, Morton TH. Proton-bound dimers of 1-methylcytosine and its derivatives: vibrational and NMR spectroscopy. Phys Chem Chem Phys 2014; 15:19001-12. [PMID: 24096726 DOI: 10.1039/c3cp52260a] [Citation(s) in RCA: 13] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/30/2022]
Abstract
Vibrational spectroscopy and NMR demonstrate that the proton-bound dimer of 1-methylcytosine, 1, has an unsymmetrical structure at room temperature. In the gas phase, investigation of isolated homodimer 1 reveals five fundamental NH vibrations by IR Multiple Photon Dissociation (IRMPD) action spectroscopy. The NH···N stretching vibration between the two ring nitrogens exhibits a frequency of 1570 cm(-1), as confirmed by examination of the proton-bound homodimers of 5-fluoro-1-methycytosine, 2, and of 1,5-dimethylcytosine, 3, which display absorptions in the same region that disappear upon deuterium substitution. (13)C, and (15)N NMR of the solid iodide salt of 1 confirm the nonequivalence of the two rings in the anhydrous proton-bound homodimer at room temperature. IRMPD spectra of the three possible heterodimers also show NH···N stretches in the same domain, and at least one of the heterodimers, the proton-bound dimer of 1,5-dimethylcytosine with 1-methylcytosine, exhibits two bands suggestive of the presence of two tautomers close in energy.
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Affiliation(s)
- Hou U Ung
- Department of Chemistry, University of California, Riverside, CA 92521-0403, USA.
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25
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Li J, Li X, Iyengar SS. Vibrational Properties of Hydrogen-Bonded Systems Using the Multireference Generalization to the “On-the-Fly” Electronic Structure within Quantum Wavepacket ab Initio Molecular Dynamics (QWAIMD). J Chem Theory Comput 2014; 10:2265-80. [DOI: 10.1021/ct5002347] [Citation(s) in RCA: 11] [Impact Index Per Article: 1.1] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/30/2022]
Affiliation(s)
- Junjie Li
- Department of Chemistry and
Department of Physics, Indiana University, 800 East Kirkwood Avenue, Bloomington, Indiana 47405, United States
| | - Xiaohu Li
- Department of Chemistry and
Department of Physics, Indiana University, 800 East Kirkwood Avenue, Bloomington, Indiana 47405, United States
| | - Srinivasan S. Iyengar
- Department of Chemistry and
Department of Physics, Indiana University, 800 East Kirkwood Avenue, Bloomington, Indiana 47405, United States
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26
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Hermosilla L, Prampolini G, Calle P, García de la Vega JM, Brancato G, Barone V. Extension of the AMBER Force Field for Nitroxide Radicals and Combined QM/MM/PCM Approach to the Accurate Determination of EPR Parameters of DMPO-H in Solution. J Chem Theory Comput 2013; 9:3626-36. [PMID: 26584116 PMCID: PMC4660035 DOI: 10.1021/ct4003256] [Citation(s) in RCA: 6] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/28/2022]
Abstract
A computational strategy that combines both time-dependent and time-independent approaches is exploited to accurately model molecular dynamics and solvent effects on the isotropic hyperfine coupling constants of the DMPO-H nitroxide. Our recent general force field for nitroxides derived from AMBER ff99SB is further extended to systems involving hydrogen atoms in β-positions with respect to NO-moiety. The resulting force-field has been employed in a series of classical molecular dynamics simulations, comparing the computed EPR parameters from selected molecular configurations to the corresponding experimental data in different solvents. The effect of vibrational averaging on the spectroscopic parameters is also taken into account, by second-order vibrational perturbation theory involving semidiagonal third energy derivatives together first and second property derivatives.
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Affiliation(s)
- Laura Hermosilla
- Departamento de Química Física Aplicada, Facultad de Ciencias, Universidad Autónoma de Madrid, 28049 Madrid (Spain)
| | - Giacomo Prampolini
- Istituto per i Processi Chimico-Fisici, Consiglio Nazionale delle Ricerche, Area della Ricerca, via Moruzzi 1, I-56124, Pisa (Italy)
| | - Paloma Calle
- Departamento de Química Física Aplicada, Facultad de Ciencias, Universidad Autónoma de Madrid, 28049 Madrid (Spain)
| | | | - Giuseppe Brancato
- Scuola Normale Superiore, Piazza dei Cavalieri 7, I-56126, Pisa (Italy)
| | - Vincenzo Barone
- Scuola Normale Superiore, Piazza dei Cavalieri 7, I-56126, Pisa (Italy)
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27
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Ung HU, Moehlig AR, Khodagholian S, Berden G, Oomens J, Morton TH. Proton-Bridge Motions in Amine Conjugate Acid Ions Having Intramolecular Hydrogen Bonds to Hydroxyl and Amine Groups. J Phys Chem A 2013; 117:1360-9. [DOI: 10.1021/jp311506y] [Citation(s) in RCA: 18] [Impact Index Per Article: 1.6] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/28/2022]
Affiliation(s)
- Hou U. Ung
- Department of Chemistry, University of California, Riverside, California 92521-0403,
United States
| | - Aaron R. Moehlig
- Department of Chemistry, University of California, Riverside, California 92521-0403,
United States
| | - Sevana Khodagholian
- Department of Chemistry, University of California, Riverside, California 92521-0403,
United States
| | - Giel Berden
- FOM Institute for Plasmaphysics Rijnhuizen, Edisonbaan 14, NL-3439 MN
Nieuwegein, The Netherlands
| | - Jos Oomens
- FOM Institute for Plasmaphysics Rijnhuizen, Edisonbaan 14, NL-3439 MN
Nieuwegein, The Netherlands
- van’t Hoff Institute for
Molecular Science, University of Amsterdam, NL-1098XH, The Netherlands
| | - Thomas Hellman Morton
- Department of Chemistry, University of California, Riverside, California 92521-0403,
United States
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28
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Wang Y, Zhou J, Liu K, Dai L. Bi-SO3H-functionalized room temperature ionic liquids based on bipyridinium: highly efficient and recyclable catalysts for the synthesis of naphthalene-condensed oxazinone derivatives. RSC Adv 2013. [DOI: 10.1039/c3ra00133d] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/21/2022] Open
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29
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Dietrick SM, Iyengar SS. Constructing Periodic Phase Space Orbits from ab Initio Molecular Dynamics Trajectories to Analyze Vibrational Spectra: Case Study of the Zundel (H5O2+) Cation. J Chem Theory Comput 2012; 8:4876-90. [DOI: 10.1021/ct300695x] [Citation(s) in RCA: 17] [Impact Index Per Article: 1.4] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/29/2022]
Affiliation(s)
- Scott M. Dietrick
- Department
of Chemistry and Department of Physics, Indiana University, Bloomington, Indiana
47405, United States
| | - Srinivasan S. Iyengar
- Department
of Chemistry and Department of Physics, Indiana University, Bloomington, Indiana
47405, United States
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30
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Phatak P, Sumner I, Iyengar SS. Gauging the flexibility of the active site in soybean lipoxygenase-1 (SLO-1) through an atom-centered density matrix propagation (ADMP) treatment that facilitates the sampling of rare events. J Phys Chem B 2012; 116:10145-64. [PMID: 22838384 PMCID: PMC3558621 DOI: 10.1021/jp3015047] [Citation(s) in RCA: 25] [Impact Index Per Article: 2.1] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/29/2022]
Abstract
We present a computational methodology to sample rare events in large biological enzymes that may involve electronically polarizing, reactive processes. The approach includes simultaneous dynamical treatment of electronic and nuclear degrees of freedom, where contributions from the electronic portion are computed using hybrid density functional theory and the computational costs are reduced through a hybrid quantum mechanics/molecular mechanics (QM/MM) treatment. Thus, the paper involves a QM/MM dynamical treatment of rare events. The method is applied to probe the effect of the active site elements on the critical hydrogen transfer step in the soybean lipoxygenase-1 (SLO-1) catalyzed oxidation of linoleic acid. It is found that the dynamical fluctuations and associated flexibility of the active site are critical toward maintaining the electrostatics in the regime where the reactive process can occur smoothly. Physical constraints enforced to limit the active site flexibility are akin to mutations and, in the cases studied, have a detrimental effect on the electrostatic fluctuations, thus adversely affecting the hydrogen transfer process.
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Affiliation(s)
- Prasad Phatak
- Department of Chemistry and Department of Physics, Indiana University, 800 E. Kirkwood Ave, Bloomington, IN-47405
| | - Isaiah Sumner
- Department of Chemistry and Department of Physics, Indiana University, 800 E. Kirkwood Ave, Bloomington, IN-47405
| | - Srinivasan S. Iyengar
- Department of Chemistry and Department of Physics, Indiana University, 800 E. Kirkwood Ave, Bloomington, IN-47405
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31
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Pacheco AB, Dietrick SM, Stevens PS, Iyengar SS. "Pump-probe" atom-centered density matrix propagation studies to gauge anharmonicity and energy repartitioning in atmospheric reactive adducts: case study of the OH + isoprene and OH + butadiene reaction intermediates. J Phys Chem A 2012; 116:4108-28. [PMID: 22401490 DOI: 10.1021/jp212330e] [Citation(s) in RCA: 9] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/30/2022]
Abstract
Time-resolved "pump-probe" ab initio molecular dynamics studies are constructed to probe the stability of reaction intermediates, the mechanism of energy transfer, and energy repartitioning, for moieties involved during the interaction of volatile organic compunds with hydroxyl radical. These systems are of prime importance in the atmosphere. Specifically, the stability of reaction intermediates of hydroxyl radical adducts to isoprene and butadiene molecules is used as a case study to develop novel computational techniques involving "pump-probe" ab initio molecular dynamics. Starting with the various possible hydroxyl radical adducts to isoprene and butadiene, select vibrational modes of each of the adducts are populated with excess energy to mimic the initial conditions of an experiment. The flow of energy into the remaining modes is then probed by subjecting the excited adducts to ab initio molecular dynamics simulations. It is found that the stability of the adducts arises directly due to the anhormonically driven coupling of the modes to facilitate repartitioning of the excess vibrational energy. This kind of vibrational repartitioning has a critical influence on the energy density.
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Affiliation(s)
- Alexander B Pacheco
- Department of Chemistry, Indiana University, Bloomington, Indiana 47405, USA
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32
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Li X, Schatz GC, Nesbitt DJ. Anion Effects in the Scattering of CO2 from the Room-Temperature Ionic Liquids [bmim][BF4] and [bmim][Tf2N]: Insights from Quantum Mechanics/Molecular Mechanics Trajectories. J Phys Chem B 2012; 116:3587-602. [DOI: 10.1021/jp2123357] [Citation(s) in RCA: 26] [Impact Index Per Article: 2.2] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/29/2022]
Affiliation(s)
- Xiaohu Li
- Department of Chemistry, Northwestern University, 2145 Sheridan Road, Evanston,
Illinois 60208-3113, United States
| | - George C. Schatz
- Department of Chemistry, Northwestern University, 2145 Sheridan Road, Evanston,
Illinois 60208-3113, United States
| | - David J. Nesbitt
- JILA, Campus Box 440, University of Colorado, Boulder, Colorado 80309-0440,
United States
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33
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Dietrick SM, Pacheco AB, Phatak P, Stevens PS, Iyengar SS. Influence of Water on Anharmonicity, Stability, and Vibrational Energy Distribution of Hydrogen-Bonded Adducts in Atmospheric Reactions: Case Study of the OH + Isoprene Reaction Intermediate Using Ab Initio Molecular Dynamics. J Phys Chem A 2011; 116:399-414. [DOI: 10.1021/jp204511v] [Citation(s) in RCA: 25] [Impact Index Per Article: 1.9] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/28/2022]
Affiliation(s)
- Scott M. Dietrick
- Department of Chemistry, Indiana University, Bloomington, Indiana 47405, United States
| | - Alexander B. Pacheco
- Department of Chemistry, Indiana University, Bloomington, Indiana 47405, United States
| | - Prasad Phatak
- Department of Chemistry, Indiana University, Bloomington, Indiana 47405, United States
| | - Philip S. Stevens
- Department of Chemistry and Center for Research in Environmental Science, School of Public and Environmental Affairs, Indiana University, Bloomington, Indiana 47405, United States
| | - Srinivasan S. Iyengar
- Departments of Chemistry and Physics, Indiana University, Bloomington, Indiana 47405, United States
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34
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Olesen S, Guasco T, Roscioli J, Johnson M. Tuning the intermolecular proton bond in the H5 O2+ ‘Zundel ion’ scaffold. Chem Phys Lett 2011. [DOI: 10.1016/j.cplett.2011.04.060] [Citation(s) in RCA: 48] [Impact Index Per Article: 3.7] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/26/2022]
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35
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Pathak AK, Mukherjee T, Maity DK. Structure and IR Spectra of Microhydrated Cl2 with an Excess Electron: Experiment versus Theory. J Phys Chem A 2011; 115:3559-64. [DOI: 10.1021/jp112245v] [Citation(s) in RCA: 7] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/29/2022]
Affiliation(s)
- A. K. Pathak
- Theoretical Chemistry Section, Chemistry Group, Bhabha Atomic Research Centre, Mumbai 400085, India
| | - T. Mukherjee
- Chemistry Group, Bhabha Atomic Research Centre, Mumbai 400085, India
| | - D. K. Maity
- Theoretical Chemistry Section, Chemistry Group, Bhabha Atomic Research Centre, Mumbai 400085, India
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36
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Hurtado P, Gámez F, Hamad S, Martínez-Haya B, Steill JD, Oomens J. Crown Ether Complexes with H3O+ and NH4+: Proton Localization and Proton Bridge Formation. J Phys Chem A 2011; 115:7275-82. [DOI: 10.1021/jp200481w] [Citation(s) in RCA: 50] [Impact Index Per Article: 3.8] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/21/2022]
Affiliation(s)
- Paola Hurtado
- Departamento de Sistemas Físicos, Químicos y Naturales, Universidad Pablo de Olavide, 41013 Seville, Spain
| | - F. Gámez
- Departamento de Sistemas Físicos, Químicos y Naturales, Universidad Pablo de Olavide, 41013 Seville, Spain
| | - Said Hamad
- Departamento de Sistemas Físicos, Químicos y Naturales, Universidad Pablo de Olavide, 41013 Seville, Spain
| | - Bruno Martínez-Haya
- Departamento de Sistemas Físicos, Químicos y Naturales, Universidad Pablo de Olavide, 41013 Seville, Spain
| | - Jeffrey D. Steill
- FOM Institute for Plasma Physics Rijnhuizen, Edisonbaan 14, NL-3439 MN Nieuwegein, The Netherlands
| | - Jos Oomens
- FOM Institute for Plasma Physics Rijnhuizen, Edisonbaan 14, NL-3439 MN Nieuwegein, The Netherlands
- University of Amsterdam, Science Park 904, 1098XH Amsterdam, The Netherlands
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37
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Li X, Iyengar SS. Quantum wavepacket ab initio molecular dynamics: generalizations using an extended Lagrangian treatment of diabatic states coupled through multireference electronic structure. J Chem Phys 2011; 133:184105. [PMID: 21073211 DOI: 10.1063/1.3504167] [Citation(s) in RCA: 14] [Impact Index Per Article: 1.1] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/14/2022] Open
Abstract
We present a generalization to our previously developed quantum wavepacket ab initio molecular dynamics (QWAIMD) method by using multiple diabatic electronic reduced single particle density matrices, propagated within an extended Lagrangian paradigm. The Slater determinantal wavefunctions associated with the density matrices utilized may be orthogonal or nonorthogonal with respect to each other. This generalization directly results from an analysis of the variance in electronic structure with quantum nuclear degrees of freedom. The diabatic electronic states are treated here as classical parametric variables and propagated simultaneously along with the quantum wavepacket and classical nuclei. Each electronic density matrix is constrained to be N-representable. Consequently two sets of new methods are derived: extended Lagrangian-QWAIMD (xLag-QWAIMD) and diabatic extended Lagrangian-QWAIMD (DxLag-QWAIMD). In both cases, the instantaneous potential energy surface for the quantum nuclear degrees of freedom is constructed from the diabatic states using an on-the-fly nonorthogonal multireference formalism. By introducing generalized grid-based electronic basis functions, we eliminate the basis set dependence on the quantum nucleus. Subsequent reuse of the two-electron integrals during the on-the-fly potential energy surface computation stage yields a substantial reduction in computational costs. Specifically, both xLag-QWAIMD and DxLag-QWAIMD turn out to be about two orders of magnitude faster than our previously developed time-dependent deterministic sampling implementation of QWAIMD. Energy conservation properties, accuracy of the associated potential surfaces, and vibrational properties are analyzed for a family of hydrogen bonded systems.
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Affiliation(s)
- Xiaohu Li
- Department of Chemistry, Indiana University, 800 E. Kirkwood Ave, Bloomington, Indiana 47405, USA
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38
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Lankau T, Yu CH. A quantum description of the proton movement in an idealized NHN+ bridge. Phys Chem Chem Phys 2011; 13:12758-69. [DOI: 10.1039/c0cp02172e] [Citation(s) in RCA: 7] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/21/2022]
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39
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Polfer NC. Infrared multiple photon dissociation spectroscopy of trapped ions. Chem Soc Rev 2011; 40:2211-21. [DOI: 10.1039/c0cs00171f] [Citation(s) in RCA: 229] [Impact Index Per Article: 17.6] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/21/2023]
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40
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Pavone M, Biczysko M, Rega N, Barone V. Magnetic Properties of Nitroxide Spin Probes: Reliable Account of Molecular Motions and Nonspecific Solvent Effects by Time-Dependent and Time-Independent Approaches. J Phys Chem B 2010; 114:11509-14. [DOI: 10.1021/jp102232c] [Citation(s) in RCA: 22] [Impact Index Per Article: 1.6] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/08/2023]
Affiliation(s)
- Michele Pavone
- Department of Chemistry “P. Corradini”, University of Napoli Federico II and CR-INSTM “Village”, Complesso Universitario Monte Sant’Angelo, Via Cintia 80126, Napoli, Italy; and Scuola Normale Superiore di Pisa, and INFN Sezione di Pisa, Piazza dei Cavalieri 7, I-56126, Pisa, Italy
| | - Malgorzata Biczysko
- Department of Chemistry “P. Corradini”, University of Napoli Federico II and CR-INSTM “Village”, Complesso Universitario Monte Sant’Angelo, Via Cintia 80126, Napoli, Italy; and Scuola Normale Superiore di Pisa, and INFN Sezione di Pisa, Piazza dei Cavalieri 7, I-56126, Pisa, Italy
| | - Nadia Rega
- Department of Chemistry “P. Corradini”, University of Napoli Federico II and CR-INSTM “Village”, Complesso Universitario Monte Sant’Angelo, Via Cintia 80126, Napoli, Italy; and Scuola Normale Superiore di Pisa, and INFN Sezione di Pisa, Piazza dei Cavalieri 7, I-56126, Pisa, Italy
| | - Vincenzo Barone
- Department of Chemistry “P. Corradini”, University of Napoli Federico II and CR-INSTM “Village”, Complesso Universitario Monte Sant’Angelo, Via Cintia 80126, Napoli, Italy; and Scuola Normale Superiore di Pisa, and INFN Sezione di Pisa, Piazza dei Cavalieri 7, I-56126, Pisa, Italy
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41
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Li X, Oomens J, Eyler JR, Moore DT, Iyengar SS. Isotope dependent, temperature regulated, energy repartitioning in a low-barrier, short-strong hydrogen bonded cluster. J Chem Phys 2010; 132:244301. [DOI: 10.1063/1.3430525] [Citation(s) in RCA: 43] [Impact Index Per Article: 3.1] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/14/2022] Open
Affiliation(s)
- Xiaohu Li
- Department of Chemistry, Indiana University, 800 E. Kirkwood Ave., Bloomington, Indiana 47405, USA
| | - Jos Oomens
- FOM Institute for Plasma Physics ‘Rijnhuizen’, Edisonbaan 14, 3439 MN Nieuwegein, The Netherlands
| | - John R. Eyler
- Department of Chemistry, University of Florida, Gainesville, Florida 32611, USA
| | - David T. Moore
- Department of Chemistry, Lehigh University, Bethlehem, Pennsylvania 18015, USA
| | - Srinivasan S. Iyengar
- Department of Chemistry, Indiana University, 800 E. Kirkwood Ave., Bloomington, Indiana 47405, USA
- Department of Physics, Indiana University, 727 E. Third St., Bloomington, Indiana 47405, USA
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42
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Fridgen TD. Infrared consequence spectroscopy of gaseous protonated and metal ion cationized complexes. MASS SPECTROMETRY REVIEWS 2009; 28:586-607. [PMID: 19343731 DOI: 10.1002/mas.20224] [Citation(s) in RCA: 135] [Impact Index Per Article: 9.0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 05/17/2023]
Abstract
In this article, the new and exciting techniques of infrared consequence spectroscopy (sometimes called action spectroscopy) of gaseous ions are reviewed. These techniques include vibrational predissociation spectroscopy and infrared multiple photon dissociation spectroscopy and they typically complement one another in the systems studied and the information gained. In recent years infrared consequence spectroscopy has provided long-awaited direct evidence into the structures of gaseous ions from organometallic species to strong ionic hydrogen bonded structures to large biomolecules. Much is being learned with respect to the structures of ions without their stabilizing solvent which can be used to better understand the effect of solvent on their structures. This review mainly covers the topics with which the author has been directly involved in research: structures of proton-bound dimers, protonated amino acids and DNA bases, amino acid and DNA bases bound to metal ions and, more recently, solvated ionic complexes. It is hoped that this review reveals the impact that infrared consequence spectroscopy has had on the field of gaseous ion chemistry.
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Affiliation(s)
- Travis D Fridgen
- Department of Chemistry, Memorial University of Newfoundland, St. John's, Newfoundland and Labrador, Canada A1B 3X7.
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43
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Polfer NC, Oomens J. Vibrational spectroscopy of bare and solvated ionic complexes of biological relevance. MASS SPECTROMETRY REVIEWS 2009; 28:468-494. [PMID: 19241457 DOI: 10.1002/mas.20215] [Citation(s) in RCA: 261] [Impact Index Per Article: 17.4] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 05/25/2023]
Abstract
The low density of ions in mass spectrometers generally precludes direct infrared (IR) absorption measurements. The IR spectrum of an ion can nonetheless be obtained by inducing photodissociation of the ion using a high-intensity tunable laser. The emergence of free electron lasers (FELs) and recent breakthroughs in bench-top lasers based on nonlinear optics have now made it possible to routinely record IR spectra of gas-phase ions. As the energy of one IR photon is insufficient to cause dissociation of molecules and strongly bound complexes, two main experimental strategies have been developed to effect photodissociation. In infrared multiple-photon dissociation (IR-MPD) many photons are absorbed resonantly and their energy is stored in the bath of vibrational modes, leading to dissociation. In the "messenger" technique a weakly bound van der Waals atom is detached upon absorption of a single photon. Fundamental, historical, and practical aspects of these methods will be presented. Both of these approaches make use of very different methods of ion preparation and manipulation. While in IR-MPD ions are irradiated in trapping mass spectrometers, the "messenger" technique is generally carried out in molecular beam instruments. The main focus of this review is the application of IR spectroscopy to biologically relevant molecular systems (amino acids, peptides, proteins). Particular issues that will be addressed here include gas-phase zwitterions, the (chemical) structures of peptides and their collision-induced dissociation (CID) products, IR spectra of gas-phase proteins, and the chelation of metal-ligand complexes. Another growing area of research is IR spectroscopy on solvated clusters, which offer a bridge between the gas-phase and solution environments. The development of state-of-the-art computational approaches has gone hand-in-hand with advances in experimental techniques. The main advantage of gas-phase cluster research, as opposed to condensed-phase experiments, is that the systems of interest can be understood in detail and structural effects can be studied in isolation. It will be shown that IR spectroscopy of mass-selected (bio)molecular systems is now well-placed to address specific questions on the individual effect of charge carriers (protons and metal ions), as well as solvent molecules on the overall structure.
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Affiliation(s)
- Nick C Polfer
- Chemistry Department, University of Florida, Gainesville, Florida 32611, USA.
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44
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Kaledin M, Moffitt JM, Clark CR, Rizvi F. Ab Initio Molecular Dynamics Simulations of the Infrared Spectra of H3O2− and D3O2−. J Chem Theory Comput 2009; 5:1328-36. [DOI: 10.1021/ct8004485] [Citation(s) in RCA: 18] [Impact Index Per Article: 1.2] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/28/2022]
Affiliation(s)
- Martina Kaledin
- Chemistry and Biochemistry, Kennesaw State University, 1000 Chastain Rd., Box 1203, Kennesaw, Georgia 30144
| | - John M. Moffitt
- Chemistry and Biochemistry, Kennesaw State University, 1000 Chastain Rd., Box 1203, Kennesaw, Georgia 30144
| | - Craig R. Clark
- Chemistry and Biochemistry, Kennesaw State University, 1000 Chastain Rd., Box 1203, Kennesaw, Georgia 30144
| | - Fareeha Rizvi
- Chemistry and Biochemistry, Kennesaw State University, 1000 Chastain Rd., Box 1203, Kennesaw, Georgia 30144
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45
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Bush MF, Oomens J, Williams ER. Proton affinity and zwitterion stability: new results from infrared spectroscopy and theory of cationized lysine and analogues in the gas phase. J Phys Chem A 2009; 113:431-8. [PMID: 19128186 DOI: 10.1021/jp807470p] [Citation(s) in RCA: 50] [Impact Index Per Article: 3.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/29/2022]
Abstract
The gas-phase structures of alkali metal cationized lysine (Lys), alpha-N-methyllysine (NMeLys), and epsilon-N,N-dimethyllysine (Lys(Me)(2)) are investigated using infrared multiple photon dissociation (IRMPD) spectroscopy utilizing light generated by a free electron laser and ab initio calculations. The proton affinities of the compounds span a range of approximately 20 kJ/mol. For NMeLys x M(+), experiment and theory indicate that NMeLys is nonzwitterionic for M = Li and zwitterionic for M = Na and K. For Lys(Me)(2) x M(+), experiment and theory indicate that Lys(Me)(2) is zwitterionic for M = Li, Na, and K. This is the first spectroscopic observation of the zwitterionic form of an amino acid complexed with Li(+). The results are compared with IRMPD spectra reported previously for Lys and -N-methyllysine (Lys(Me)) complexed with Li, Na, and K, and new calculations performed at higher levels of theory for those ions. The combined experimental and theoretical results indicate that protonation in the zwitterionic forms of the these amino acids is favored at the more basic methylated amine site, but that any relationship between the proton affinity of the amino acid and the relative zwitterion stability of the alkali metal cationized amino acid is only indirect. These results provide additional evidence that proton affinities are not a reliable indicator of zwitterion stability for cationized amino acids because side chains can have very different effects on the stability of different conformers in the neutral, protonated, and metal cationized forms.
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Affiliation(s)
- Matthew F Bush
- Department of Chemistry, University of California, Berkeley, California 94720-1460, USA
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46
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Oomens J, Steill JD, Redlich B. Gas-Phase IR Spectroscopy of Deprotonated Amino Acids. J Am Chem Soc 2009; 131:4310-9. [DOI: 10.1021/ja807615v] [Citation(s) in RCA: 155] [Impact Index Per Article: 10.3] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/29/2022]
Affiliation(s)
- Jos Oomens
- FOM Institute for Plasma Physics “Rijnhuizen”, Edisonbaan 14, 3439MN Nieuwegein, The Netherlands
| | - Jeffrey D. Steill
- FOM Institute for Plasma Physics “Rijnhuizen”, Edisonbaan 14, 3439MN Nieuwegein, The Netherlands
| | - Britta Redlich
- FOM Institute for Plasma Physics “Rijnhuizen”, Edisonbaan 14, 3439MN Nieuwegein, The Netherlands
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47
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Gardenier GH, Roscioli JR, Johnson MA. Intermolecular Proton Binding in the Presence of a Large Electric Dipole: Ar-Tagged Vibrational Predissociation Spectroscopy of the CH3CN·H+·OH2 and CH3CN·D+·OD2 Complexes. J Phys Chem A 2008; 112:12022-6. [DOI: 10.1021/jp800948s] [Citation(s) in RCA: 27] [Impact Index Per Article: 1.7] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/03/2023]
Affiliation(s)
- George H. Gardenier
- Sterling Chemistry Laboratory, Department of Chemistry, Yale University, P.O. Box 208107, New Haven, Connecticut 06520
| | - Joseph R. Roscioli
- Sterling Chemistry Laboratory, Department of Chemistry, Yale University, P.O. Box 208107, New Haven, Connecticut 06520
| | - Mark A. Johnson
- Sterling Chemistry Laboratory, Department of Chemistry, Yale University, P.O. Box 208107, New Haven, Connecticut 06520
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48
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Sumner I, Iyengar SS. Combining quantum wavepacketab initiomolecular dynamics with QM/MM and QM/QM techniques: Implementation blendingONIOMand empirical valence bond theory. J Chem Phys 2008; 129:054109. [DOI: 10.1063/1.2956496] [Citation(s) in RCA: 25] [Impact Index Per Article: 1.6] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/24/2022] Open
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