1
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Tokmachev AM. Networks of Hydrogen Bond Networks in Water Clusters. J Phys Chem A 2024; 128:2763-2771. [PMID: 38536704 DOI: 10.1021/acs.jpca.4c00892] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 04/12/2024]
Abstract
Water clusters play a prominent role in atmospheric and solution chemistry. Numerous arrangements of protons, H-bond configurations or networks, shape the cluster properties. Studies of small water clusters by cryogenic scanning tunneling microscopy and high-resolution rovibrational spectroscopy have established proton rearrangement mechanisms forming pathways between H-bond networks. The mechanisms, concerted tunneling in particular, describe the local processes connecting pairs of configurations. Here, proton rearrangement networks mapping these transformations are defined and explored to provide a global view of the H-bond configurations in clusters. The networks are constructed for clusters of different sizes and structures. Their analysis reveals an odd-even effect with respect to the number of water molecules, exponential growth of the small-world character, bimodality of the degree distributions, and gapped assortativity of the networks. The last two properties signify the unexpected division of H-bond configurations into two classes according to their network connectivity. The results demonstrate qualitative differences between proton rearrangement mechanisms, suggest a strong influence of the cluster structure. The generated networks are of interest as real-world models for network rewiring; they establish an alternative platform for studies of proton rearrangements in H-bonded systems.
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Affiliation(s)
- Andrey M Tokmachev
- National Research Center "Kurchatov Institute", Kurchatov Sq. 1, Moscow 123182, Russia
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2
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Arandhara M, Ramesh SG. Nuclear Quantum Effects in Hydroxide Hydrate Along the H-Bond Bifurcation Pathway. J Phys Chem A 2024; 128:1600-1610. [PMID: 38393819 DOI: 10.1021/acs.jpca.3c08027] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 02/25/2024]
Abstract
Path integral (PI) simulations are used to explore nuclear quantum effects (NQEs) in hydroxide hydrate and its perdeuterated isotopomer along the H-bond bifurcation pathway. Toward this, a new potential energy surface using the symmetric gradient domain machine learning method with ab initio data at the CCSD(T)/aug-cc-pVTZ level is built. From PI umbrella sampling (US) simulations, free energy profiles along the bifurcation coordinate are explored as a function of temperature. At ambient temperature, the bifurcation barrier is increased upon inclusion of NQEs. At low temperatures in the deep tunneling regime, the barrier is strongly decreased and flattened. These trends are examined, and the role of the O-O distance is also investigated through two-dimensional US simulations.
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Affiliation(s)
- Mrinal Arandhara
- Department of Inorganic and Physical Chemistry, Indian Institute of Science, Bangalore 560012, India
| | - Sai G Ramesh
- Department of Inorganic and Physical Chemistry, Indian Institute of Science, Bangalore 560012, India
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3
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Méndez E, Videla PE, Laria D. Collective Proton Transfers in Cyclic Water-Ammonia Tetramers: A Path Integral Machine-Learning Study. J Phys Chem A 2023; 127:1839-1848. [PMID: 36794937 DOI: 10.1021/acs.jpca.2c07994] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 02/17/2023]
Abstract
We present results from machine-learning-based path integral molecular dynamics simulations that describe isomerization paths articulated via collective proton transfers along mixed, cyclic tetramers combining water and ammonia at cryogenic conditions. The net result of such isomerizations is a reverse of the chirality of the global hydrogen-bonding architecture along the different cyclic moieties. In monocomponent tetramers, the classical free energy profiles associated with these isomerizations present the usual symmetric double-well characteristics whereas the reactive paths exhibit full concertedness among the different intermolecular transfer processes. Contrastingly, in mixed water/ammonia tetramers, the incorporation of a second component introduces imbalances in the strengths of the different hydrogen bonds leading to a partial loss of concertedness, most notably at the vicinity of the transition state. As such, the highest and lowest degrees of progression are registered along OH···N and O···HN coordinations, respectively. These characteristics lead to polarized transition state scenarios akin to solvent-separated ion-pair configurations. The explicit incorporation of nuclear quantum effects promotes drastic depletions in the activation free energies and modifications in the overall shape of the profiles which include central plateau-like stages, indicating the prevalence of deep tunneling regimes. On the other hand, the quantum treatment of the nuclei partially restores the degree of concertedness among the evolutions of the individual transfers.
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Affiliation(s)
- Emilio Méndez
- Departamento de Química Inorgánica, Analítica y Química-Física and INQUIMAE-CONICET, Facultad de Ciencias Exactas y Naturales, Universidad de Buenos Aires Ciudad Universitaria, Pabellón II, 1428 Buenos Aires, Argentina
| | - Pablo E Videla
- Department of Chemistry and Energy Sciences Institute, Yale University, 225 Prospect Street, New Haven, Connecticut 06520, United States
| | - Daniel Laria
- Departamento de Química Inorgánica, Analítica y Química-Física and INQUIMAE-CONICET, Facultad de Ciencias Exactas y Naturales, Universidad de Buenos Aires Ciudad Universitaria, Pabellón II, 1428 Buenos Aires, Argentina.,Departamento de Física de la Materia Condensada, Comisión Nacional de Energía Atómica, Avenida Libertador 8250, 1429 Buenos Aires, Argentina
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4
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Méndez E, Videla PE, Laria D. Equilibrium and Dynamical Characteristics of Hydrogen Bond Bifurcations in Water-Water and Water-Ammonia Dimers: A Path Integral Molecular Dynamics Study. J Phys Chem A 2022; 126:4721-4733. [PMID: 35834556 DOI: 10.1021/acs.jpca.2c02525] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/29/2022]
Abstract
We present path integral molecular dynamics results that describe the effects of nuclear quantum fluctuations on equilibrium and dynamical characteristics pertaining to bifurcation pathways in hydrogen bonded dimers combining water and ammonia, at cryogenic temperatures of the order of 20 K. Along these isomerizations, the hydrogen atoms in the molecules acting as hydrogen-bond donors interchange their original dangling/connective characters. Our results reveal that the resulting quantum transition paths comprise three stages: the initial and final ones involve overall rotations during which the two protons retain their classical-like characteristics. Effects from quantum fluctuation are clearly manifested in the changes operated at the intermediate passages over transition states, as the spatial extents of the protons stretch over typical lengths comparable to the distances between connective and dangling basins of attractions. Consequently, the classical over-the-hill path is replaced by a tunneling controlled mechanism which, within the path integral perspective, can be cast in terms of concerted inter-basin migrations of polymer beads from dangling-to-connective and from connective-to-dangling, at practically no energy costs. We also estimated the characteristic timescales describing such interconversions within the approximate ring polymer rate theory. Effects derived from full and partial deuteration are also discussed.
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Affiliation(s)
- Emilio Méndez
- Departamento de Química Inorgánica, Analítica y Química-Física and INQUIMAE-CONICET, Facultad de Ciencias Exactas y Naturales, Universidad de Buenos Aires Ciudad Universitaria, Pabellón II, 1428 Buenos Aires, Argentina
| | - Pablo E Videla
- Department of Chemistry and Energy Sciences Institute, Yale University, 225 Prospect Street, New Haven, Connecticut 06520, United States
| | - Daniel Laria
- Departamento de Física de la Materia Condensada, Comisión Nacional de Energía Atómica, Avenida Libertador 8250, 1429 Buenos Aires, Argentina
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5
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Cheng YH, Zhu YC, Kang W, Li X, Fang W. Determination of concerted or stepwise mechanism of hydrogen tunneling from isotope effects: Departure between experiment and theory. J Chem Phys 2022; 156:124304. [DOI: 10.1063/5.0085010] [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
Isotope substitution is an important experimental technique that offers deep insight into reaction mechanisms, as the measured kinetic isotope effects (KIEs) can be directly compared with theory. For multiple proton transfer processes, there are two types of mechanisms: stepwise transfer and concerted transfer. The Bell-Limbach model provides a simple theory to determine whether the proton transfer mechanism is stepwise or concerted from KIEs. Recent STM experiments have studied the proton switching process in water tetramers on NaCl(001). Theoretical studies predict that this process occurs via a concerted mechanism, however, the experimental KIEs resemble the Bell-Limbach model for stepwise tunneling, raising question on the underlying mechanism or the validity of the model. We study this system using ab initio instanton theory, and in addition to thermal rates, we also considered microcanonical rates, as well as tunneling splittings. Instanton theory predicts a concerted mechanism, and the KIEs for tunneling rates (both thermal and microcanonical) upon deuteration are consistent with the Bell-Limbach model for concerted tunneling, but could not explain the experiments. For tunneling splittings, partial and full deuteration changes the size of it in a similar fashion to how it changes the rates. We further examined the Bell-Limbach model in another system, porphycene, which has both stepwise and concerted tunneling pathways. The KIEs predicted by instanton theory are again consistent with the Bell-Limbach model. This study highlights differences between KIEs in stepwise and concerted tunneling, and the discrepancy between theory and recent STM experiments. New theory/experiments are desired to settle this problem.
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Affiliation(s)
| | | | - Wei Kang
- Center for Applied Physics and Technology, Peking University, China
| | | | - Wei Fang
- Dalian Institute of Chemical Physics, China
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6
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Miller SL, Wiebenga-Sanford BP, Rithner CD, Levinger NE. Nanoconfinement Raises the Energy Barrier to Hydrogen Atom Exchange between Water and Glucose. J Phys Chem B 2021; 125:3364-3373. [PMID: 33784460 DOI: 10.1021/acs.jpcb.0c10681] [Citation(s) in RCA: 3] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/30/2022]
Abstract
In bulk aqueous environments, the exchange of protons between labile hydroxyl groups typically occurs easily and quickly. Nanoconfinement can dramatically change this normally facile process. Through exchange spectroscopy (EXSY) NMR measurements, we observe that nanoconfinement of glucose and water within AOT (sodium bis(2-ethylhexyl) sulfosuccinate) reverse micelles raises the energy barrier to labile hydrogen exchange, which suggests a disruption of the hydrogen bond network. Near room temperature, we measure barriers high enough to slow the process by as much as 2 orders of magnitude. Although exchange rates slow with decreasing temperatures in these nanoconfined environments, the barrier we measure below ∼285 K is 3-5 times lower than the barrier measured at room temperature, indicating a change in mechanism for the process. These findings suggest the possibility of hydrogen tunneling at a surprisingly high-temperature threshold. Furthermore, differences in exchange rates depend on the hydroxyl group position on the glucose pyranose ring and suggest a net orientation of glucose at the reverse micelle interface.
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Affiliation(s)
- Samantha L Miller
- Department of Chemistry, Colorado State University, Fort Collins, Colorado 80523-1872, United States
| | | | - Christopher D Rithner
- Department of Chemistry, Colorado State University, Fort Collins, Colorado 80523-1872, United States
| | - Nancy E Levinger
- Department of Chemistry, Colorado State University, Fort Collins, Colorado 80523-1872, United States
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7
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Dagys L, Klimkevičius V, Klimavicius V, Balčiūnas S, Banys J, Balevicius V. Cross‐polarization with magic‐angle spinning kinetics and impedance spectroscopy study of proton mobility, local disorder, and thermal equilibration in
hydrogen‐bonded
poly(methacrylic acid). JOURNAL OF POLYMER SCIENCE 2020. [DOI: 10.1002/pol.20200592] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/08/2023]
Affiliation(s)
- Laurynas Dagys
- Institute of Chemical Physics Vilnius University Vilnius Lithuania
- Department of Chemistry University of Southampton Southampton UK
| | | | - Vytautas Klimavicius
- Institute of Chemical Physics Vilnius University Vilnius Lithuania
- Eduard‐Zintl Institute for Inorganic and Physical Chemistry University of Technology Darmstadt Darmstadt Germany
| | - Sergejus Balčiūnas
- Institute of Applied Electrodynamics and Telecommunications Vilnius University Vilnius Lithuania
| | - Jūras Banys
- Institute of Applied Electrodynamics and Telecommunications Vilnius University Vilnius Lithuania
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8
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Turi L, Rodriguez J, Laria D. Combined Effects from Solvation and Nuclear Quantum Fluctuations on Autoionization Mechanisms in Aqueous Clusters. J Phys Chem B 2020; 124:2198-2208. [PMID: 32075372 DOI: 10.1021/acs.jpcb.9b11087] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/28/2022]
Abstract
Using path-integral molecular dynamics simulations, we examine isomerization paths involving collective proton transfers in [H2O]5 and [H2O]8 clusters under cryogenic conditions. We focused attention on combined effects derived from solvation and nuclear quantum fluctuations on the characteristics of free energy barriers and relative stabilities of reactants and products. In particular, we analyzed two different processes: the first one involves the exchange of donor-acceptor hydrogen bond roles along cyclic moieties, whereas the second one corresponds to charge separation leading to stable [H3O]+[OH]- ion pairs. In the first case, the explicit incorporation of quantum tunneling introduces important modifications in the classical free energy profile. The resulting quantum profile presents two main contributions, one corresponding to compressions of O-O distances and a second one ascribed to nuclear tunneling of the light protons. Solvation effects promote a moderate polarization of the cyclic structures and a partial loss of concertedness in the collective modes, most notably, at the onset of tunneling. Still, the latter effects are also sufficiently strong to promote the stabilization of ion pairs along the classical trajectories. In contrast, the explicit incorporation of nuclear quantum fluctuations leads to charge separated configurations that are marginally stable. As such, the latter states could also be regarded as short-lived intermediate states along the reactive exchange path.
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Affiliation(s)
- László Turi
- Institute of Chemistry, Eötvös Loránd University, P.O. Box 32, Budapest, 112 H-1518, Hungary
| | - Javier Rodriguez
- Departamento de Fı́sica de la Materia Condensada, Comisión Nacional de Energı́a Atómica, Avenida Libertador 8250, 1429 Buenos Aires, Argentina.,ECyT, UNSAM, Martı́n de Irigoyen 3100, 1650 San Martı́n, Provincia de Buenos Aires, Argentina
| | - Daniel Laria
- Departamento de Fı́sica de la Materia Condensada, Comisión Nacional de Energı́a Atómica, Avenida Libertador 8250, 1429 Buenos Aires, Argentina.,Departamento de Quı́mica Inorgánica, Analı́tica y Quı́mica-Fı́sica and INQUIMAE-CONICET, Facultad de Ciencias Exactas y Naturales, Universidad de Buenos Aires Ciudad Universitaria, Pabellón II, 1428 Buenos Aires, Argentina
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9
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Sakti AW, Nishimura Y, Nakai H. Recent advances in quantum‐mechanical molecular dynamics simulations of proton transfer mechanism in various water‐based environments. WIRES COMPUTATIONAL MOLECULAR SCIENCE 2020. [DOI: 10.1002/wcms.1419] [Citation(s) in RCA: 5] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 11/07/2022]
Affiliation(s)
- Aditya W. Sakti
- Element Strategy Initiative for Catalysts and Batteries (ESICB) Kyoto University Kyoto Japan
| | - Yoshifumi Nishimura
- Waseda Research Institute for Science and Engineering (WISE) Waseda University Tokyo Japan
| | - Hiromi Nakai
- Element Strategy Initiative for Catalysts and Batteries (ESICB) Kyoto University Kyoto Japan
- Waseda Research Institute for Science and Engineering (WISE) Waseda University Tokyo Japan
- Department of Chemistry and Biochemistry, School of Advanced Science and Engineering Waseda University Tokyo Japan
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10
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Tabacchi G, Fabbiani M, Mino L, Martra G, Fois E. The Case of Formic Acid on Anatase TiO 2 (101): Where is the Acid Proton? Angew Chem Int Ed Engl 2019; 58:12431-12434. [PMID: 31310450 DOI: 10.1002/anie.201906709] [Citation(s) in RCA: 50] [Impact Index Per Article: 10.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/29/2019] [Indexed: 01/20/2023]
Abstract
Carboxylic-acid adsorption on anatase TiO2 is a relevant process in many technological applications. Yet, despite several decades of investigations, the acid-proton localization-either on the molecule or on the surface-is still an open issue. By modeling the adsorption of formic acid on top of anatase(101) surfaces, we highlight the formation of a short strong hydrogen bond. In the 0 K limit, the acid-proton behavior is ruled by quantum delocalization effects in a single potential well, while at ambient conditions, the proton undergoes a rapid classical shuttling in a shallow two-well free-energy profile. This picture, supported by agreement with available experiments, shows that the anatase surface acts like a protecting group for the carboxylic acid functionality. Such a new conceptual insight might help rationalize chemical processes involving carboxylic acids on oxide surfaces.
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Affiliation(s)
- Gloria Tabacchi
- Department of Science and High Technology, University of Insubria and INSTM, via Valleggio 9, I-22100, Como, Italy
| | - Marco Fabbiani
- Department of Chemistry and Nanostructured Interfaces and Surfaces NIS interdepartmental centre, University of Torino, via P. Giuria 7, I-10125, Torino, Italy
| | - Lorenzo Mino
- Department of Chemistry and Nanostructured Interfaces and Surfaces NIS interdepartmental centre, University of Torino, via P. Giuria 7, I-10125, Torino, Italy
| | - Gianmario Martra
- Department of Chemistry and Nanostructured Interfaces and Surfaces NIS interdepartmental centre, University of Torino, via P. Giuria 7, I-10125, Torino, Italy
| | - Ettore Fois
- Department of Science and High Technology, University of Insubria and INSTM, via Valleggio 9, I-22100, Como, Italy
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11
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Tabacchi G, Fabbiani M, Mino L, Martra G, Fois E. The Case of Formic Acid on Anatase TiO
2
(101): Where is the Acid Proton? Angew Chem Int Ed Engl 2019. [DOI: 10.1002/ange.201906709] [Citation(s) in RCA: 6] [Impact Index Per Article: 1.2] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/08/2022]
Affiliation(s)
- Gloria Tabacchi
- Department of Science and High TechnologyUniversity of Insubria and INSTM via Valleggio 9 I-22100 Como Italy
| | - Marco Fabbiani
- Department of Chemistry and Nanostructured Interfaces and Surfaces NIS interdepartmental centreUniversity of Torino via P. Giuria 7 I-10125 Torino Italy
| | - Lorenzo Mino
- Department of Chemistry and Nanostructured Interfaces and Surfaces NIS interdepartmental centreUniversity of Torino via P. Giuria 7 I-10125 Torino Italy
| | - Gianmario Martra
- Department of Chemistry and Nanostructured Interfaces and Surfaces NIS interdepartmental centreUniversity of Torino via P. Giuria 7 I-10125 Torino Italy
| | - Ettore Fois
- Department of Science and High TechnologyUniversity of Insubria and INSTM via Valleggio 9 I-22100 Como Italy
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12
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13
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Carnevale D, Pelupessy P, Bodenhausen G. Cross-term Splittings Due to the Orientational Inequivalence of Proton Magnetic Shielding Tensors: Do Water Molecules Trapped in Crystals Hop or Tunnel? J Phys Chem Lett 2019; 10:3224-3231. [PMID: 31059264 DOI: 10.1021/acs.jpclett.9b00914] [Citation(s) in RCA: 4] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 06/09/2023]
Abstract
Water molecules trapped in crystals of barium chlorate monohydrate have been investigated by magic-angle spinning (MAS) proton NMR spectroscopy in the temperature range 110-300 K. At high temperatures, a single spinning sideband pattern is observed. Below 150 K, however, two interleaved spinning sideband manifolds appear, with distinct centerbands that do not coincide with the average isotropic chemical shift seen at high temperatures. This hitherto unknown "cross-term splitting" results from the interplay of the homonuclear dipole-dipole coupling and two anisotropic proton shielding tensors that have identical principal components but nonequivalent orientations. The resulting cross terms cannot be averaged out by rotation about the magic angle. The analysis of the exchange-induced broadening, coalescence, and narrowing of the cross-term splitting in MAS spectra allows one to estimate the rate of exchange of the two protons between 140 and 190 K. The experimental data is compared with 2H and 1H NMR studies of the same sample reported in the literature. Density functional theory methods are utilized to estimate the thermal activation energy for a 2-fold hopping process of proton exchange about the H-O-H bisector. The Bell-Limbach model allows one to take into account contributions due to incoherent quantum tunneling in the low-temperature regime.
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Affiliation(s)
- Diego Carnevale
- Laboratoire des Biomolécules, LBM, Département de Chimie , École Normale Supérieure , PSL University, Sorbonne Université, CNRS, 75005 Paris , France
| | - Philippe Pelupessy
- Laboratoire des Biomolécules, LBM, Département de Chimie , École Normale Supérieure , PSL University, Sorbonne Université, CNRS, 75005 Paris , France
| | - Geoffrey Bodenhausen
- Laboratoire des Biomolécules, LBM, Département de Chimie , École Normale Supérieure , PSL University, Sorbonne Université, CNRS, 75005 Paris , France
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14
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Michaelian K, Padilla NS. UVC photon-induced denaturing of DNA: A possible dissipative route to Archean enzyme-less replication. Heliyon 2019; 5:e01902. [PMID: 31249892 PMCID: PMC6584779 DOI: 10.1016/j.heliyon.2019.e01902] [Citation(s) in RCA: 6] [Impact Index Per Article: 1.2] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/01/2018] [Revised: 04/16/2019] [Accepted: 05/31/2019] [Indexed: 01/01/2023] Open
Abstract
Non-equilibrium thermodynamics is a relevant framework from within which to address formidable difficulties encountered in explaining the origin of life; from molecular synthesis and complexation, enzyme-less proliferation, to evolution (including the acquisition of homochirality and information). From within this framework we have proposed that the origin of life was the origin of the dissipative structuring of organic pigments which became the fundamental molecules of life (e.g. RNA and DNA) proliferated through autocatalytic photochemical reactions under the thermodynamic imperative of dissipating the imposed UVC solar photon flux available at the Archean surface. Here we present experimental evidence demonstrating that the absorption and dissipation of UVC light by synthetic DNA of 25 base pairs (and also natural salmon sperm DNA) over a range of temperatures, including below their melting temperature, leads to denaturing. Since denaturing is a non-trivial step on route to enzyme-less replication, our data suggest the possibility of a dissipative route to DNA replication at the origin of life. Such a dissipation-replication relation provides a simple mechanism for the early accumulation of both homochirality and information. Possible mechanisms of UVC photon-induced denaturing of DNA are discussed.
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Affiliation(s)
- Karo Michaelian
- Department of Nuclear Physics and Application of Radiation, Institute of Physics, UNAM, Cto. Interior de la Investigación Científica, Ciudad Universitaria, Cuidad de México, C.P. 04510, Mexico
| | - Norberto Santillán Padilla
- Faculty of Science, UNAM, Cto. Interior de la Investigación Científica, Ciudad Universitaria, Cuidad de México, C.P. 04510, Mexico
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15
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Dammak H, Brieuc F, Geneste G, Torrent M, Hayoun M. Isotope effect on hydrogen bond symmetrization in hydrogen and deuterium fluoride crystals by molecular dynamics simulation. Phys Chem Chem Phys 2019; 21:3211-3217. [PMID: 30681084 DOI: 10.1039/c8cp06949b] [Citation(s) in RCA: 4] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/31/2022]
Abstract
The isotope effect on the collective proton/deuteron transfer in hydrogen and deuterium fluoride crystals has been investigated at 100 K by ab initio quantum-thermal-bath path-integral molecular dynamics (QTB-PIMD) simulation. The deuterons within a planar zigzag chain of the orthorhombic structure simultaneously flip between covalent and hydrogen bonds due to the barrier crossing through tunnelling. The height of the corresponding static barrier normalized for one deuteron is 29.2 meV. In the HF crystal, all the protons are located at the center of the heavy-atom distance. This evidences the symmetrization of the H-bonds, and indicates that the proton zero-point energy is above the barrier top. The decrease of the heavy-atom distance due to quantum fluctuations in both HF and DF crystals corresponds to a large decrease and an increase of the hydrogen and covalent bond lengths, respectively. Upon deuteration, the increase of the heavy-atom distance (Ubbelohde effect) is in agreement with experimental data.
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Affiliation(s)
- Hichem Dammak
- Laboratoire Structures Propriétés et Modélisation des Solides, CentraleSupélec, CNRS, Université Paris-Saclay, F 91190 Gif-sur-Yvette, France.
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16
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Sun CQ. Unprecedented O:⇔:O compression and H↔H fragilization in Lewis solutions. Phys Chem Chem Phys 2019; 21:2234-2250. [DOI: 10.1039/c8cp06910g] [Citation(s) in RCA: 21] [Impact Index Per Article: 4.2] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/21/2023]
Abstract
Charge injection in terms of protons, lone pairs, cations and anions by acid and base solvation mediates the HB network and properties of Lewis solutions through H↔H fragilization, O:⇔:O compression and polarization, ionic polarization and hydrating H2O dipolar screen shielding, anion–anion repulsion, compressed solvent H–O bond elongation and undercoordinated solute H–O bond contraction.
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Affiliation(s)
- Chang Q. Sun
- EBEAM
- Yangtze Normal University
- Chongqing 408100
- China
- NOVITUS
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17
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Sun CQ. Aqueous charge injection: solvation bonding dynamics, molecular nonbond interactions, and extraordinary solute capabilities. INT REV PHYS CHEM 2018. [DOI: 10.1080/0144235x.2018.1544446] [Citation(s) in RCA: 16] [Impact Index Per Article: 2.7] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/26/2022]
Affiliation(s)
- Chang Q. Sun
- EBEAM, Yangtze Normal University, Chongqing, People's Republic of China
- NOVITAS, EEE, Nanyang Technological University, Singapore, Singapore
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18
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Vasylieva A, Doroshenko I, Vaskivskyi Y, Chernolevska Y, Pogorelov V. FTIR study of condensed water structure. J Mol Struct 2018. [DOI: 10.1016/j.molstruc.2018.05.002] [Citation(s) in RCA: 12] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/07/2023]
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19
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Feng Y, Wang Z, Guo J, Chen J, Wang EG, Jiang Y, Li XZ. The collective and quantum nature of proton transfer in the cyclic water tetramer on NaCl(001). J Chem Phys 2018; 148:102329. [PMID: 29544296 DOI: 10.1063/1.5004737] [Citation(s) in RCA: 7] [Impact Index Per Article: 1.2] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/14/2022] Open
Abstract
Proton tunneling is an elementary process in the dynamics of hydrogen-bonded systems. Collective tunneling is known to exist for a long time. Atomistic investigations of this mechanism in realistic systems, however, are scarce. Using a combination of ab initio theoretical and high-resolution experimental methods, we investigate the role played by the protons on the chirality switching of a water tetramer on NaCl(001). Our scanning tunneling spectroscopies show that partial deuteration of the H2O tetramer with only one D2O leads to a significant suppression of the chirality switching rate at a cryogenic temperature (T), indicating that the chirality switches by tunneling in a concerted manner. Theoretical simulations, in the meantime, support this picture by presenting a much smaller free-energy barrier for the translational collective proton tunneling mode than other chirality switching modes at low T. During this analysis, the virial energy provides a reasonable estimator for the description of the nuclear quantum effects when a traditional thermodynamic integration method cannot be used, which could be employed in future studies of similar problems. Given the high-dimensional nature of realistic systems and the topology of the hydrogen-bonded network, collective proton tunneling may exist more ubiquitously than expected. Systems of this kind can serve as ideal platforms for studies of this mechanism, easily accessible to high-resolution experimental measurements.
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Affiliation(s)
- Yexin Feng
- International Center for Quantum Materials and School of Physics, Peking University, Beijing 100871, People's Republic of China
| | - Zhichang Wang
- International Center for Quantum Materials and School of Physics, Peking University, Beijing 100871, People's Republic of China
| | - Jing Guo
- International Center for Quantum Materials and School of Physics, Peking University, Beijing 100871, People's Republic of China
| | - Ji Chen
- International Center for Quantum Materials and School of Physics, Peking University, Beijing 100871, People's Republic of China
| | - En-Ge Wang
- International Center for Quantum Materials and School of Physics, Peking University, Beijing 100871, People's Republic of China
| | - Ying Jiang
- International Center for Quantum Materials and School of Physics, Peking University, Beijing 100871, People's Republic of China
| | - Xin-Zheng Li
- International Center for Quantum Materials and School of Physics, Peking University, Beijing 100871, People's Republic of China
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20
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Sun CQ, Chen J, Gong Y, Zhang X, Huang Y. (H, Li)Br and LiOH Solvation Bonding Dynamics: Molecular Nonbond Interactions and Solute Extraordinary Capabilities. J Phys Chem B 2018; 122:1228-1238. [DOI: 10.1021/acs.jpcb.7b09269] [Citation(s) in RCA: 25] [Impact Index Per Article: 4.2] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 02/07/2023]
Affiliation(s)
- Chang Q. Sun
- Chongqing
Key Laboratory of Extraordinary Coordination Bond and Advanced Materials
Technologies (EBEAM), Yangtze Normal University, Chongqing 408100, China
- School
EEE, Nanyang Technological University, Singapore 639798
| | - Jiasheng Chen
- Key
Laboratory of Low-Dimensional Materials and Application Technologies
(Ministry of Education) and School of Materials, Science and Engineering, Xiangtan University, Hunan 411105, China
| | - Yinyan Gong
- Institute
of Coordination Bond Metrology and Engineering (CBME), China Jiliang University, Hangzou 310018, China
| | - Xi Zhang
- Institute
of Nanosurface Science and Engineering, Shenzhen University, Shenzhen 518060, China
| | - Yongli Huang
- Key
Laboratory of Low-Dimensional Materials and Application Technologies
(Ministry of Education) and School of Materials, Science and Engineering, Xiangtan University, Hunan 411105, China
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