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Zunzunegui-Bru E, Gruber E, Lázaro T, Bartolomei M, Hernández MI, Campos-Martínez J, González-Lezana T, Bergmeister S, Zappa F, Scheier P, Pérez de Tudela R, Hernández-Rojas J, Bretón J. Observation of Multiple Ordered Solvation Shells in Doped Helium Droplets: The Case of He NCa 2. J Phys Chem Lett 2023; 14:3126-3131. [PMID: 36952614 PMCID: PMC10084467 DOI: 10.1021/acs.jpclett.3c00224] [Citation(s) in RCA: 1] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Grants] [Track Full Text] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 05/04/2023]
Abstract
In this Letter, we report the experimental detection of likely the largest ordered structure of helium atoms surrounding a monatomic impurity observed to date using a recently developed technique. The mass spectrometry investigation of HeNCa2+ clusters, formed in multiply charged helium nanodroplets, reveals magic numbers at N = 12, 32, 44, and 74. Classical optimization and path integral Monte Carlo calculations suggest the existence of up to four shells surrounding the calcium dication which are closed with well-ordered Mozartkugel-like structures: He12Ca2+ with an icosahedron, the second at He32Ca2+ with a dodecahedron, the third at He44Ca2+ with a larger icosahedron, and finally for He74Ca2+, we find that the outermost He atoms form an icosidodecahedron which contains the other inner shells. We analyze the reasons for the formation of such ordered shells in order to guide the selection of possible candidates to exhibit a similar behavior.
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Affiliation(s)
- Eva Zunzunegui-Bru
- Instituto de Física Fundamental, IFF-CSIC, Serrano 123, Madrid 28006, Spain
| | - Elisabeth Gruber
- Institut für Ionenphysik und Angewandte Physik, Universität Innsbruck, Technikerstraße 25, Innsbruck 6020, Austria
| | - Teresa Lázaro
- Instituto de Física Fundamental, IFF-CSIC, Serrano 123, Madrid 28006, Spain
| | | | - Marta I Hernández
- Instituto de Física Fundamental, IFF-CSIC, Serrano 123, Madrid 28006, Spain
| | | | | | - Stefan Bergmeister
- Institut für Ionenphysik und Angewandte Physik, Universität Innsbruck, Technikerstraße 25, Innsbruck 6020, Austria
| | - Fabio Zappa
- Institut für Ionenphysik und Angewandte Physik, Universität Innsbruck, Technikerstraße 25, Innsbruck 6020, Austria
| | - Paul Scheier
- Institut für Ionenphysik und Angewandte Physik, Universität Innsbruck, Technikerstraße 25, Innsbruck 6020, Austria
| | | | - Javier Hernández-Rojas
- Departamento de Física and IUdEA, Universidad de La Laguna, La Laguna, 38205, Tenerife, Spain
| | - José Bretón
- Departamento de Física and IUdEA, Universidad de La Laguna, La Laguna, 38205, Tenerife, Spain
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2
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Schwaab G, Pérez de Tudela R, Mani D, Pal N, Roy TK, Gabas F, Conte R, Durán Caballero L, Ceotto M, Marx D, Havenith M. Zwitter Ionization of Glycine at Outer Space Conditions due to Microhydration by Six Water Molecules. Phys Rev Lett 2022; 128:033001. [PMID: 35119904 DOI: 10.1103/physrevlett.128.033001] [Citation(s) in RCA: 3] [Impact Index Per Article: 1.5] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Received: 02/27/2021] [Revised: 08/09/2021] [Accepted: 12/04/2021] [Indexed: 06/14/2023]
Abstract
We investigate glycine microsolvation with water molecules, mimicking astrophysical conditions, in our laboratory by embedding these clusters in helium nanodroplets at 0.37 K. We recorded mass selective infrared spectra in the frequency range 1500-1800 cm^{-1} where two bands centered at 1630 and 1724 cm^{-1} were observed. By comparison with the extensive accompanying calculations, the band at 1630 cm^{-1} was assigned to the COO^{-} asymmetric stretching mode of the zwitter ion and the band at 1724 cm^{-1} was assigned to redshifted C=O stretch within neutral clusters. We show that zwitter ion formation of amino acids readily occurs with only few water molecules available even under extreme conditions.
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Affiliation(s)
- Gerhard Schwaab
- Lehrstuhl für Physikalische Chemie II, Ruhr-Universität Bochum, 44780 Bochum, Germany
| | | | - Devendra Mani
- Department of Chemistry, Indian Institute of Technology Kanpur, Uttar Pradesh 208016, India
| | - Nitish Pal
- Lehrstuhl für Physikalische Chemie II, Ruhr-Universität Bochum, 44780 Bochum, Germany
| | - Tarun Kumar Roy
- Lehrstuhl für Physikalische Chemie II, Ruhr-Universität Bochum, 44780 Bochum, Germany
| | - Fabio Gabas
- Dipartimento di Chimica, Università degli Studi di Milano, 20133 Milano, Italy
| | - Riccardo Conte
- Dipartimento di Chimica, Università degli Studi di Milano, 20133 Milano, Italy
| | | | - Michele Ceotto
- Dipartimento di Chimica, Università degli Studi di Milano, 20133 Milano, Italy
| | - Dominik Marx
- Lehrstuhl für Theoretische Chemie, Ruhr-Universität Bochum, 44780 Bochum, Germany
| | - Martina Havenith
- Lehrstuhl für Physikalische Chemie II, Ruhr-Universität Bochum, 44780 Bochum, Germany
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3
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Tripathi R, Durán Caballero L, Pérez de Tudela R, Hölzl C, Marx D. Unveiling Zwitterionization of Glycine in the Microhydration Limit. ACS Omega 2021; 6:12676-12683. [PMID: 34056419 PMCID: PMC8154221 DOI: 10.1021/acsomega.1c00869] [Citation(s) in RCA: 4] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Grants] [Track Full Text] [Download PDF] [Figures] [Subscribe] [Scholar Register] [Received: 02/17/2021] [Accepted: 03/24/2021] [Indexed: 06/12/2023]
Abstract
Charge separation under solvation stress conditions is a fundamental process that comes in many forms in doped water clusters. Yet, the mechanism of intramolecular charge separation, where constraints due to the molecular structure might be intricately tied to restricted solvation structures, remains largely unexplored. Microhydrated amino acids are such paradigmatic molecules. Ab initio simulations are carried out at 300 K in the frameworks of metadynamics sampling and thermodynamic integration to map the thermal mechanisms of zwitterionization using Gly(H2O) n with n = 4 and 10. In both cases, a similar water-mediated proton transfer chain mechanism is observed; yet, detailed analyses of thermodynamics and kinetics demonstrate that the charge-separated zwitterion is the preferred species only for n = 10 mainly due to kinetic stabilization. Structural analyses disclose that bifurcated H-bonded water bridges, connecting the cationic and anionic sites in the fluctuating microhydration network at room temperature, are enhanced in the transition-state ensemble exclusively for n = 10 and become overwhelmingly abundant in the stable zwitterion. The findings offer potential insights into charge separation under solvation stress conditions beyond the present example.
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4
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Pérez de Tudela R, Marx D. Generating Excess Protons in Microsolvated Acid Clusters under Ambient Conditions: An Issue of Configurational Entropy versus Internal Energy. Chemistry 2020; 26:11955-11959. [PMID: 32080914 PMCID: PMC7540491 DOI: 10.1002/chem.202000864] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/17/2020] [Indexed: 11/29/2022]
Abstract
Acid dissociation, and thus liberation of excess protons in small water droplets, impacts on diverse fields such as interstellar, atmospheric or environmental chemistry. At cryogenic temperatures below 1 K, it is now well established that as few as four water molecules suffice to dissociate the generic strong acid HCl, yet temperature-driven recombination sets in simply upon heating that cluster. Here, the fundamental question is posed of how many more water molecules are required to stabilize a hydrated excess proton at room temperature. Ab initio path integral simulations disclose that not five, but six water molecules are needed at 300 K to allow for HCl dissociation independently from nuclear quantum effects. In order to provide the molecular underpinnings of these observations, the classical and quantum free energy profiles were decomposed along the dissociation coordinate in terms of the corresponding internal energy and entropy profiles. What decides in the end about acid dissociation, and thus ion pair formation, in a specific microsolvated water cluster at room temperature is found to be a fierce competition between classical configurational entropy and internal energy, where the former stabilizes the undissociated state whereas the latter favors dissociation. It is expected that these are generic findings with broad implications on acid-base chemistry depending on temperature in small water assemblies.
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Affiliation(s)
| | - Dominik Marx
- Lehrstuhl für Theoretische ChemieRuhr-Universität Bochum44780BochumGermany
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5
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Mani D, de Tudela RP, Schwan R, Pal N, Körning S, Forbert H, Redlich B, van der Meer AFG, Schwaab G, Marx D, Havenith M. Acid solvation versus dissociation at "stardust conditions": Reaction sequence matters. Sci Adv 2019; 5:eaav8179. [PMID: 31187059 PMCID: PMC6555628 DOI: 10.1126/sciadv.aav8179] [Citation(s) in RCA: 18] [Impact Index Per Article: 3.6] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Received: 10/23/2018] [Accepted: 05/02/2019] [Indexed: 05/09/2023]
Abstract
Chemical reactions at ultralow temperatures are of fundamental importance to primordial molecular evolution as it occurs on icy mantles of dust nanoparticles or on ultracold water clusters in dense interstellar clouds. As we show, studying reactions in a stepwise manner in ultracold helium nanodroplets by mass-selective infrared (IR) spectroscopy provides an avenue to mimic these "stardust conditions" in the laboratory. In our joint experimental/theoretical study, in which we successively add H2O molecules to HCl, we disclose a unique IR fingerprint at 1337 cm-1 that heralds hydronium (H3O+) formation and, thus, acid dissociation generating solvated protons. In stark contrast, no reaction is observed when reversing the sequence by allowing HCl to interact with preformed small embryonic ice-like clusters. Our ab initio simulations demonstrate that not only reaction stoichiometry but also the reaction sequence needs to be explicitly considered to rationalize ultracold chemistry.
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Affiliation(s)
- Devendra Mani
- Lehrstuhl für Physikalische Chemie II, Ruhr-Universität Bochum, 44801 Bochum, Germany
| | | | - Raffael Schwan
- Lehrstuhl für Physikalische Chemie II, Ruhr-Universität Bochum, 44801 Bochum, Germany
| | - Nitish Pal
- Lehrstuhl für Physikalische Chemie II, Ruhr-Universität Bochum, 44801 Bochum, Germany
| | - Saskia Körning
- Lehrstuhl für Theoretische Chemie, Ruhr-Universität Bochum, 44780 Bochum, Germany
| | - Harald Forbert
- Lehrstuhl für Theoretische Chemie, Ruhr-Universität Bochum, 44780 Bochum, Germany
| | - Britta Redlich
- FELIX Laboratory, Institute for Molecules and Materials, Radboud University, 6325 ED Nijmegen, Netherlands
| | - A. F. G. van der Meer
- FELIX Laboratory, Institute for Molecules and Materials, Radboud University, 6325 ED Nijmegen, Netherlands
| | - Gerhard Schwaab
- Lehrstuhl für Physikalische Chemie II, Ruhr-Universität Bochum, 44801 Bochum, Germany
| | - Dominik Marx
- Lehrstuhl für Theoretische Chemie, Ruhr-Universität Bochum, 44780 Bochum, Germany
- Corresponding author. (M.H.); (D.M.)
| | - Martina Havenith
- Lehrstuhl für Physikalische Chemie II, Ruhr-Universität Bochum, 44801 Bochum, Germany
- Corresponding author. (M.H.); (D.M.)
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Pérez de Tudela R, Martini P, Goulart M, Scheier P, Pirani F, Hernández-Rojas J, Bretón J, Ortiz de Zárate J, Bartolomei M, González-Lezana T, Hernández MI, Campos-Martínez J, Villarreal P. A combined experimental and theoretical investigation of Cs + ions solvated in He N clusters. J Chem Phys 2019; 150:154304. [PMID: 31005067 DOI: 10.1063/1.5092566] [Citation(s) in RCA: 16] [Impact Index Per Article: 3.2] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/18/2023] Open
Abstract
Solvation of Cs+ ions inside helium droplets has been investigated both experimentally and theoretically. On the one hand, mass spectra of doped helium clusters ionized with a crossed electron beam, HeNCs+, have been recorded for sizes up to N = 60. The analysis of the ratio between the observed peaks for each size N reveals evidences of the closure of the first solvation shell when 17 He atoms surround the alkali ion. On the other hand, we have obtained energies and geometrical structures of the title clusters by means of basin-hopping, diffusion Monte Carlo (DMC), and path integral Monte Carlo (PIMC) methods. The analytical He-Cs+ interaction potential employed in our calculations is represented by the improved Lennard-Jones expression optimized on high level ab initio energies. The weakness of the existing interaction between helium and Cs+ in comparison with some other alkali ions such as Li+ is found to play a crucial role. Our theoretical findings confirm that the first solvation layer is completed at N = 17 and both evaporation and second difference energies obtained with the PIMC calculation seem to reproduce a feature observed at N = 12 for the experimental ion abundance. The analysis of the DMC probability distributions reveals the important contribution from the icosahedral structure to the overall configuration for He12Cs+.
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Affiliation(s)
| | - Paul Martini
- Institut für Ionenphysik und Angewandte Physik, Universität Innsbruck, Technikerstr. 25, A-6020 Innsbruck, Austria
| | - Marcelo Goulart
- Institut für Ionenphysik und Angewandte Physik, Universität Innsbruck, Technikerstr. 25, A-6020 Innsbruck, Austria
| | - Paul Scheier
- Institut für Ionenphysik und Angewandte Physik, Universität Innsbruck, Technikerstr. 25, A-6020 Innsbruck, Austria
| | - Fernando Pirani
- Dipartimento di Chimica, Biologia e Biotecnologie, Universitá di Perugia, 06123 Perugia, Italy
| | - Javier Hernández-Rojas
- Departamento de Física and IUdEA, Universidad de La Laguna, La Laguna, 38205 Tenerife, Spain
| | - José Bretón
- Departamento de Física and IUdEA, Universidad de La Laguna, La Laguna, 38205 Tenerife, Spain
| | | | | | | | - Marta I Hernández
- Instituto de Física Fundamental, IFF-CSIC, Serrano 123, 28006 Madrid, Spain
| | | | - Pablo Villarreal
- Instituto de Física Fundamental, IFF-CSIC, Serrano 123, 28006 Madrid, Spain
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7
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Ortiz de Zárate J, Bartolomei M, González-Lezana T, Campos-Martínez J, Hernández MI, Pérez de Tudela R, Hernández-Rojas J, Bretón J, Pirani F, Kranabetter L, Martini P, Kuhn M, Laimer F, Scheier P. Snowball formation for Cs + solvation in molecular hydrogen and deuterium. Phys Chem Chem Phys 2019; 21:15662-15668. [PMID: 31271179 DOI: 10.1039/c9cp02017a] [Citation(s) in RCA: 5] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/18/2023]
Abstract
Interactions of atomic cations with molecular hydrogen are of interest for a wide range of applications in hydrogen technologies. These interactions are fairly strong despite being non-covalent, hence one can ask whether hydrogen molecules would form dense, solid-like, solvation shells around the ion (snowballs) or rather a more weakly bound compound. In this work, the interactions between Cs+ and H2 are studied both experimentally and computationally. Isotopic substitution of H2 by D2 is also investigated. On the one hand, helium nanodroplets doped with cesium and hydrogen or deuterium are ionized by electron impact and the (H2/D2)nCs+ (up to n = 30) clusters formed are identified via mass spectrometry. On the other hand, a new analytical potential energy surface, based on ab initio calculations, is developed and used to study cluster energies and structures by means of classical and quantum-mechanical Monte Carlo methods. The most salient features of the measured ion abundances are remarkably mimicked by the computed evaporation energies, particularly for the clusters composed of deuterium. This result supports the reliability of the present potential energy surface and allows us to recommend its use in related systems. Clusters with either twelve H2 or D2 molecules stand out for their stability and quasi-rigid icosahedral structures. However, the first solvation shell involves thirteen or fourteen molecules for hydrogenated or deuterated clusters, respectively. This shell retains its internal structure when extra molecules are added to the second shell and is nearly solid-like, especially for the deuterated clusters. The role played by three-body induction interactions as well as the rotational degrees of freedom is analyzed and they are found to be significant (up to 15% and 18%, respectively) for the molecules belonging to the first solvation shell.
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Affiliation(s)
- Josu Ortiz de Zárate
- Instituto de Física Fundamental, Consejo Superior de Investigaciones Científicas (IFF-CSIC), Serrano 123, 28006 Madrid, Spain.
| | - Massimiliano Bartolomei
- Instituto de Física Fundamental, Consejo Superior de Investigaciones Científicas (IFF-CSIC), Serrano 123, 28006 Madrid, Spain.
| | - Tomás González-Lezana
- Instituto de Física Fundamental, Consejo Superior de Investigaciones Científicas (IFF-CSIC), Serrano 123, 28006 Madrid, Spain.
| | - José Campos-Martínez
- Instituto de Física Fundamental, Consejo Superior de Investigaciones Científicas (IFF-CSIC), Serrano 123, 28006 Madrid, Spain.
| | - Marta I Hernández
- Instituto de Física Fundamental, Consejo Superior de Investigaciones Científicas (IFF-CSIC), Serrano 123, 28006 Madrid, Spain.
| | | | - Javier Hernández-Rojas
- Departamento de Fsica and IUdEA, Universidad de La Laguna, 38205, La Laguna, Tenerife, Spain
| | - José Bretón
- Departamento de Fsica and IUdEA, Universidad de La Laguna, 38205, La Laguna, Tenerife, Spain
| | - Fernando Pirani
- Dipartimento di Chimica, Biologia e Biotecnologie, Università di Perugia, Perugia, Italy
| | - Lorenz Kranabetter
- Universität Innsbruck, Institut für Ionenphyisk und Angewandte Physik, Technikerstraße 25, 6020 Innsbruck, Austria
| | - Paul Martini
- Universität Innsbruck, Institut für Ionenphyisk und Angewandte Physik, Technikerstraße 25, 6020 Innsbruck, Austria
| | - Martin Kuhn
- Universität Innsbruck, Institut für Ionenphyisk und Angewandte Physik, Technikerstraße 25, 6020 Innsbruck, Austria
| | - Felix Laimer
- Universität Innsbruck, Institut für Ionenphyisk und Angewandte Physik, Technikerstraße 25, 6020 Innsbruck, Austria
| | - Paul Scheier
- Universität Innsbruck, Institut für Ionenphyisk und Angewandte Physik, Technikerstraße 25, 6020 Innsbruck, Austria
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8
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Rastogi M, Leidlmair C, An der Lan L, Ortiz de Zárate J, Pérez de Tudela R, Bartolomei M, Hernández MI, Campos-Martínez J, González-Lezana T, Hernández-Rojas J, Bretón J, Scheier P, Gatchell M. Lithium ions solvated in helium. Phys Chem Chem Phys 2018; 20:25569-25576. [PMID: 30112553 PMCID: PMC6194493 DOI: 10.1039/c8cp04522d] [Citation(s) in RCA: 17] [Impact Index Per Article: 2.8] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Grants] [Track Full Text] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/17/2018] [Accepted: 08/08/2018] [Indexed: 01/18/2023]
Abstract
We report on a combined experimental and theoretical study of Li+ ions solvated by up to 50 He atoms. The experiments show clear enhanced abundances associated with HenLi+ clusters where n = 2, 6, 8, and 14. We find that classical methods, e.g. basin-hopping (BH), give results that qualitatively agree with quantum mechanical methods such as path integral Monte Carlo, diffusion Monte Carlo and quantum free energy, regarding both energies and the solvation structures that are formed. The theory identifies particularly stable structures for n = 4, 6 and 8 which line up with some of the most abundant features in the experiments.
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Affiliation(s)
- Monisha Rastogi
- Institut für Ionenphysik und Angewandte Physik, Universität Innsbruck, Technikerstr. 25
,
A-6020 Innsbruck
, Austria
.
| | - Christian Leidlmair
- Institut für Ionenphysik und Angewandte Physik, Universität Innsbruck, Technikerstr. 25
,
A-6020 Innsbruck
, Austria
.
| | - Lukas An der Lan
- Institut für Ionenphysik und Angewandte Physik, Universität Innsbruck, Technikerstr. 25
,
A-6020 Innsbruck
, Austria
.
| | - Josu Ortiz de Zárate
- Instituto de Física Fundamental, IFF-CSIC
, Serrano 123
,
28006 Madrid
, Spain
.
| | | | | | - Marta I. Hernández
- Instituto de Física Fundamental, IFF-CSIC
, Serrano 123
,
28006 Madrid
, Spain
.
| | - José Campos-Martínez
- Instituto de Física Fundamental, IFF-CSIC
, Serrano 123
,
28006 Madrid
, Spain
.
| | | | | | - José Bretón
- Departamento de Física and IUdEA, Universidad de La Laguna
,
38205 Tenerife
, Spain
| | - Paul Scheier
- Institut für Ionenphysik und Angewandte Physik, Universität Innsbruck, Technikerstr. 25
,
A-6020 Innsbruck
, Austria
.
| | - Michael Gatchell
- Institut für Ionenphysik und Angewandte Physik, Universität Innsbruck, Technikerstr. 25
,
A-6020 Innsbruck
, Austria
.
- Department of Physics, Stockholm University
,
106 91 Stockholm
, Sweden
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Pérez de Tudela R, Marx D. Publisher's Note: Acid Dissociation in HCl-Water Clusters is Temperature Dependent and Cannot be Detected Based on Dipole Moments [Phys. Rev. Lett. 119, 223001 (2017)]. Phys Rev Lett 2017; 119:259901. [PMID: 29303300 DOI: 10.1103/physrevlett.119.259901] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Received: 12/13/2017] [Indexed: 06/07/2023]
Abstract
This corrects the article DOI: 10.1103/PhysRevLett.119.223001.
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10
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Pérez de Tudela R, Marx D. Acid Dissociation in HCl-Water Clusters is Temperature Dependent and Cannot be Detected Based on Dipole Moments. Phys Rev Lett 2017; 119:223001. [PMID: 29286767 DOI: 10.1103/physrevlett.119.223001] [Citation(s) in RCA: 10] [Impact Index Per Article: 1.4] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Received: 07/24/2017] [Indexed: 05/09/2023]
Abstract
The dissociation of acids in aqueous environments at low temperatures in the presence of a limited amount of water is underlying a wealth of processes from atmospheric to interstellar science. For the paradigmatic case of HCl(H_{2}O)_{n} clusters, our extensive ab initio path integral simulations quantify in terms of free energy differences and barriers that n=4 water molecules are indeed required to dissociate HCl at low temperatures. Increasing the temperature, however, reverses the process and thus counteracts dissociation by fluctuation-driven recombination. The size of the electric dipole moment is shown to not correlate with the acid being in its dissociated or molecular state, thus rendering its measurement as a function of n unable to detect the dissociation transition.
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Affiliation(s)
| | - Dominik Marx
- Lehrstuhl für Theoretische Chemie, Ruhr-Universität Bochum, 44780 Bochum, Germany
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11
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Rodríguez-Cantano R, Bartolomei M, Hernández MI, Campos-Martínez J, González-Lezana T, Villarreal P, Pérez de Tudela R, Pirani F, Hernández-Rojas J, Bretón J. Comparative investigation of pure and mixed rare gas atoms on coronene molecules. J Chem Phys 2017; 146:034302. [DOI: 10.1063/1.4973890] [Citation(s) in RCA: 14] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/19/2022] Open
Affiliation(s)
| | | | - Marta I. Hernández
- Instituto de Física Fundamental, IFF-CSIC, Serrano 123, 28006 Madrid, Spain
| | | | | | - Pablo Villarreal
- Instituto de Física Fundamental, IFF-CSIC, Serrano 123, 28006 Madrid, Spain
| | | | - Fernando Pirani
- Dipartimento di Chimica, Biologia e Biotecnologie, Universitá di Perugia, 06123 Perugia, Italy
| | | | - José Bretón
- Departamento de Física and IUdEA, Universidad de La Laguna, 38205 Tenerife, Spain
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12
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Bartolomei M, Pérez de Tudela R, Arteaga K, González-Lezana T, Hernández MI, Campos-Martínez J, Villarreal P, Hernández-Rojas J, Bretón J, Pirani F. Adsorption of molecular hydrogen on coronene with a new potential energy surface. Phys Chem Chem Phys 2017; 19:26358-26368. [DOI: 10.1039/c7cp03819d] [Citation(s) in RCA: 17] [Impact Index Per Article: 2.4] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/21/2022]
Abstract
Adsorption of molecular hydrogen on coronene studied with a new potential energy surface. Path integral Monte Carlo and basin-hopping calculations have been performed to investigate energies and structures of the corresponding (H2)N-coronene clusters.
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Affiliation(s)
| | | | - Kilian Arteaga
- Instituto de Física Fundamental
- IFF-CSIC
- 28006 Madrid
- Spain
| | | | | | | | | | | | - José Bretón
- Departamento de Física and IUdEA
- Universidad de La Laguna
- 38205 Tenerife
- Spain
| | - Fernando Pirani
- Dipartimento di Chimica
- Biologia e Biotecnologie
- Universitá di Perugia
- Perugia
- Italy
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13
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Abstract
Not only the question of how many water molecules are required to stabilize the physiologically relevant charge-separated zwitterionic form of amino acids upon solvation but also the stabilization mechanism is still under debate. It is well known that a water bridge connecting the carboxyl with the amino group must be established. Here, we show that this is not yet a sufficient condition to stabilize the zwitterion. Instead, the formation of a bifurcated H-bonded water wire that connects the two charged groups turns out to be the key, which explains why an unexpectedly large number of water molecules of about nine is required to enable zwitterionization of microsolvated glycine. Moreover, this bifurcated wire allows one to pinpoint a frequency window that enables the detection of zwitterionization by spectroscopy. These findings will be relevant to probe and rationalize microsolvation-induced zwitterionization of not only amino acids but of other acid/base reactions that involve somewhat distant such functional groups within the same molecule.
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Affiliation(s)
| | - Dominik Marx
- Lehrstuhl für Theoretische Chemie, Ruhr-Universität Bochum , 44780 Bochum, Germany
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Rodríguez-Cantano R, Pérez de Tudela R, Bartolomei M, Hernández MI, Campos-Martínez J, González-Lezana T, Villarreal P, Hernández-Rojas J, Bretón J. Examination of the Feynman–Hibbs Approach in the Study of NeN-Coronene Clusters at Low Temperatures. J Phys Chem A 2016; 120:5370-9. [DOI: 10.1021/acs.jpca.6b01926] [Citation(s) in RCA: 12] [Impact Index Per Article: 1.5] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/28/2022]
Affiliation(s)
| | | | | | - Marta I. Hernández
- Instituto de Física Fundamental (IFF-CSIC), Serrano 123, 28006 Madrid, Spain
| | | | | | - Pablo Villarreal
- Instituto de Física Fundamental (IFF-CSIC), Serrano 123, 28006 Madrid, Spain
| | | | - José Bretón
- Departamento
de Física and Iudea, Universidad de la Laguna, 38203 Tenerife, Spain
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Rodríguez-Cantano R, Pérez de Tudela R, Bartolomei M, Hernández MI, Campos-Martínez J, González-Lezana T, Villarreal P, Hernández-Rojas J, Bretón J. Coronene molecules in helium clusters: Quantum and classical studies of energies and configurations. J Chem Phys 2015; 143:224306. [DOI: 10.1063/1.4936414] [Citation(s) in RCA: 27] [Impact Index Per Article: 3.0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/14/2022] Open
Affiliation(s)
| | | | | | - Marta I. Hernández
- Instituto de Física Fundamental, IFF-CSIC, Serrano 123, 28006 Madrid, Spain
| | | | | | - Pablo Villarreal
- Instituto de Física Fundamental, IFF-CSIC, Serrano 123, 28006 Madrid, Spain
| | | | - José Bretón
- Departamento de Física and IUdEA, Universidad de La Laguna, 38205 Tenerife, Spain
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Pérez de Tudela R, Suleimanov YV, Richardson JO, Sáez Rábanos V, Green WH, Aoiz FJ. Stress Test for Quantum Dynamics Approximations: Deep Tunneling in the Muonium Exchange Reaction D + HMu → DMu + H. J Phys Chem Lett 2014; 5:4219-4224. [PMID: 26278957 DOI: 10.1021/jz502216g] [Citation(s) in RCA: 48] [Impact Index Per Article: 4.8] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 06/04/2023]
Abstract
Quantum effects play a crucial role in chemical reactions involving light atoms at low temperatures, especially when a light particle is exchanged between two heavier partners. Different theoretical methodologies have been developed in the last decades attempting to describe zero-point energy and tunneling effects without abandoning a classical or semiclassical framework. In this work, we have chosen the D + HMu → DMu + H reaction as a stress test system for three well-established methods: two representative versions of transition state theory (TST), canonical variational theory and semiclassical instanton, and ring polymer molecular dynamics (RPMD). These calculations will be compared with accurate quantum mechanical results. Despite its apparent simplicity, the exchange of the extremely light muonium atom (0.114 u) becomes a most challenging reaction for conventional methods. The main result of this work is that RPMD provides an overall better performance than TST-based methods for such a demanding reaction. RPMD might well turn out to be a useful tool beyond TST applicability.
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Affiliation(s)
- Ricardo Pérez de Tudela
- †Departamento de Quı́mica Fı́sica I, Facultad de CC. Quı́micas, Universidad Complutense de Madrid, 28040 Madrid, Spain
| | - Yury V Suleimanov
- ‡Computation-based Science and Technology Research Center, Cyprus Institute, 20 Kavafi Str., Nicosia 2121, Cyprus
- ∥Department of Chemical Engineering, Massachusetts Institute of Technology, Cambridge, Massachusetts 02139, United States
| | - Jeremy O Richardson
- ¶Institut für Theoretische Physik und Interdisziplinäres Zentrum für Molekulare Materialien, Friedrich-Alexander-Universität Erlangen-Nürnberg (FAU), 91058 Erlangen, Germany
| | - Vicente Sáez Rábanos
- §Departamento de Quı́mica y Bioquı́mica, ETS Ingenieros de Montes, Universidad Politécnica, 28040 Madrid, Spain
| | - William H Green
- ∥Department of Chemical Engineering, Massachusetts Institute of Technology, Cambridge, Massachusetts 02139, United States
| | - F J Aoiz
- †Departamento de Quı́mica Fı́sica I, Facultad de CC. Quı́micas, Universidad Complutense de Madrid, 28040 Madrid, Spain
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Pérez de Tudela R, Barragán P, Valdés Á, Prosmiti R. Energetics and solvation structure of a dihalogen dopant (I2) in (4)He clusters. J Phys Chem A 2014; 118:6492-500. [PMID: 24869502 DOI: 10.1021/jp502994g] [Citation(s) in RCA: 13] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/30/2022]
Abstract
The energetics and structure of small HeNI2 clusters are analyzed as the size of the system changes, with N up to 38. The full interaction between the I2 molecule and the He atoms is based on analytical ab initio He-I2 potentials plus the He-He interaction, obtained from first-principle calculations. The most stable structures, as a function of the number of solvent He atoms, are obtained by employing an evolutionary algorithm and compared with CCSD(T) and MP2 ab initio computations. Further, the classical description is completed by explicitly including thermal corrections and quantum features, such as zero-point-energy values and spatial delocalization. From quantum PIMC calculations, the binding energies and radial/angular probability density distributions of the thermal equilibrium state for selected-size clusters are computed at a low temperature. The sequential formation of regular shell structures is analyzed and discussed for both classical and quantum treatments.
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Barragán P, Pérez de Tudela R, Qu C, Prosmiti R, Bowman JM. Full-dimensional quantum calculations of the dissociation energy, zero-point, and 10 K properties of H7+/D7+ clusters using an ab initio potential energy surface. J Chem Phys 2014; 139:024308. [PMID: 23862944 DOI: 10.1063/1.4812557] [Citation(s) in RCA: 9] [Impact Index Per Article: 0.9] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/14/2022] Open
Abstract
Diffusion Monte Carlo (DMC) and path-integral Monte Carlo computations of the vibrational ground state and 10 K equilibrium state properties of the H7 (+)/D7 (+) cations are presented, using an ab initio full-dimensional potential energy surface. The DMC zero-point energies of dissociated fragments H5 (+)(D5 (+))+H2(D2) are also calculated and from these results and the electronic dissociation energy, dissociation energies, D0, of 752 ± 15 and 980 ± 14 cm(-1) are reported for H7 (+) and D7 (+), respectively. Due to the known error in the electronic dissociation energy of the potential surface, these quantities are underestimated by roughly 65 cm(-1). These values are rigorously determined for first time, and compared with previous theoretical estimates from electronic structure calculations using standard harmonic analysis, and available experimental measurements. Probability density distributions are also computed for the ground vibrational and 10 K state of H7 (+) and D7 (+). These are qualitatively described as a central H3 (+)/D3 (+) core surrounded by "solvent" H2/D2 molecules that nearly freely rotate.
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Affiliation(s)
- Patricia Barragán
- Instituto de Física Fundamental, IFF-CSIC, Serrano 123, 28006 Madrid, Spain
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Suleimanov YV, de Tudela RP, Jambrina PG, Castillo JF, Sáez-Rábanos V, Manolopoulos DE, Aoiz FJ. A ring polymer molecular dynamics study of the isotopologues of the H + H2 reaction. Phys Chem Chem Phys 2013; 15:3655-65. [DOI: 10.1039/c2cp44364c] [Citation(s) in RCA: 60] [Impact Index Per Article: 5.5] [Reference Citation Analysis] [What about the content of this article? (0)] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/21/2022]
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Pérez de Tudela R, Aoiz FJ, Suleimanov YV, Manolopoulos DE. Chemical Reaction Rates from Ring Polymer Molecular Dynamics: Zero Point Energy Conservation in Mu + H2 → MuH + H. J Phys Chem Lett 2012; 3:493-497. [PMID: 26286053 DOI: 10.1021/jz201702q] [Citation(s) in RCA: 86] [Impact Index Per Article: 7.2] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 06/04/2023]
Abstract
A fundamental issue in the field of reaction dynamics is the inclusion of the quantum mechanical (QM) effects such as zero point energy (ZPE) and tunneling in molecular dynamics simulations, and in particular in the calculation of chemical reaction rates. In this work we study the chemical reaction between a muonium atom and a hydrogen molecule. The recently developed ring polymer molecular dynamics (RPMD) technique is used, and the results are compared with those of other methods. For this reaction, the thermal rate coefficients calculated with RPMD are found to be in excellent agreement with the results of an accurate QM calculation. The very minor discrepancies are within the convergence error even at very low temperatures. This exceptionally good agreement can be attributed to the dominant role of ZPE in the reaction, which is accounted for extremely well by RPMD. Tunneling only plays a minor role in the reaction.
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Affiliation(s)
- Ricardo Pérez de Tudela
- †Departamento de Química Física I, Facultad de CC. Químicas, Universidad Complutense de Madrid, 28040 Madrid, Spain
| | - F J Aoiz
- †Departamento de Química Física I, Facultad de CC. Químicas, Universidad Complutense de Madrid, 28040 Madrid, Spain
| | - Yury V Suleimanov
- ‡Physical and Theoretical Chemistry Laboratory, University of Oxford, South Parks Road, Oxford OX1 3QZ, United Kingdom
| | - David E Manolopoulos
- ‡Physical and Theoretical Chemistry Laboratory, University of Oxford, South Parks Road, Oxford OX1 3QZ, United Kingdom
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Pérez de Tudela R, López-Durán D, González-Lezana T, Delgado-Barrio G, Villarreal P, Gianturco FA, Yurtsever E. Quantum features of a barely bound molecular dopant: Cs2(3Σu) in bosonic helium droplets of variable size. J Phys Chem A 2011; 115:6892-902. [PMID: 21585200 DOI: 10.1021/jp111825n] [Citation(s) in RCA: 17] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/28/2022]
Abstract
We present in this work the study of small (4)He(N)-Cs(2)((3)Σ(u)) aggregates (2 ≤ N ≤ 30) through combined variational, diffusion Monte Carlo (DMC), and path integral Monte Carlo (PIMC) calculations. The full surface is modeled as an addition of He-Cs(2) interactions and He-He potentials. Given the negligible strength and large range of the He-Cs(2) interaction as compared with the one for He-He, a propensity of the helium atoms to pack themselves together, leaving outside the molecular dopant is to be expected. DMC calculations determine the onset of helium gathering at N = 3. To analyze energetic and structural properties as a function of N, PIMC calculations with no bosonic exchange, i.e., Boltzmann statistics, at low temperatures are carried out. At T = 0.1 K, although acceptable one-particle He-Cs(2) distributions are obtained, two-particle He-He distributions are not well described, indicating that the proper symmetry should be taken into account. PIMC distributions at T = 1 K already compare well with DMC ones and show minor exchange effects, although binding energies are still far from having converged in terms of the number of quantum beads. As N increases, the He-He PIMC pair correlation function shows a clear tendency to coincide with the experimental boson-liquid helium one at that temperature. It supports the picture of a helium droplet which carries the molecular impurity on its surface, as found earlier for other triplet dimers.
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de Tudela RP, Barragán P, Prosmiti R, Villarreal P, Delgado-Barrio G. Internal proton transfer and H2 rotations in the H5(+) cluster: a marked influence on its thermal equilibrium state. J Phys Chem A 2011; 115:2483-8. [PMID: 21391537 DOI: 10.1021/jp200392w] [Citation(s) in RCA: 30] [Impact Index Per Article: 2.3] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/29/2022]
Abstract
Classical and path integral Monte Carlo (CMC, PIMC) "on the fly" calculations are carried out to investigate anharmonic quantum effects on the thermal equilibrium structure of the H5(+) cluster. The idea to follow in our computations is based on using a combination of the above-mentioned nuclear classical and quantum statistical methods, and first-principles density functional (DFT) electronic structure calculations. The interaction energies are computed within the DFT framework using the B3(H) hybrid functional, specially designed for hydrogen-only systems. The global minimum of the potential is predicted to be a nonplanar configuration of C(2v) symmetry, while the next three low-lying stationary points on the surface correspond to extremely low-energy barriers for the internal proton transfer and to the rotation of the H2 molecules, around the C2 axis of H5(+), connecting the symmetric C(2v) minima in the planar and nonplanar orientations. On the basis of full-dimensional converged PIMC calculations, results on the quantum vibrational zero-point energy (ZPE) and state of H5(+) are reported at a low temperature of 10 K, and the influence of the above-mentioned topological features of the surface on its probability distributions is clearly demonstrated.
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Bargueño P, de Tudela RP, Miret-Artés S, Gonzalo I. An alternative route to detect parity violating energy differences through Bose–Einstein condensation of chiral molecules. Phys Chem Chem Phys 2011; 13:806-10. [DOI: 10.1039/c0cp00907e] [Citation(s) in RCA: 13] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [What about the content of this article? (0)] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/16/2023]
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Abstract
Electroweak parity violating interaction between supernova (SN) neutrinos and electrons of a simple chiral molecule is studied related to the origin of molecular homochirality. Appearance of supernova remnants inside molecular clouds favours the interaction of SN-neutrinos with interstellar molecules, leading to a energetic difference between the two enantiomers of the order of 10(-5) eV. This energetic difference is closer to the thermic energy of the interstellar medium, so molecular homochirality could be enhanced in molecular clouds containing supernova remnants inside it due to neutrino interaction.
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Affiliation(s)
- Pedro Bargueño
- Instituto de Matemáticas y Física Fundamental, Consejo Superior de Investigaciones Científicas, Serrano 123, 28006-Madrid, Spain.
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