1
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Horn KP, Vazquez-Salazar LI, Koch CP, Meuwly M. Improving potential energy surfaces using measured Feshbach resonance states. SCIENCE ADVANCES 2024; 10:eadi6462. [PMID: 38427733 PMCID: PMC10906917 DOI: 10.1126/sciadv.adi6462] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Received: 08/10/2023] [Accepted: 01/29/2024] [Indexed: 03/03/2024]
Abstract
The structure and dynamics of a molecular system is governed by its potential energy surface (PES), representing the total energy as a function of the nuclear coordinates. Obtaining accurate potential energy surfaces is limited by the exponential scaling of Hilbert space, restricting quantitative predictions of experimental observables from first principles to small molecules with just a few electrons. Here, we present an explicitly physics-informed approach for improving and assessing the quality of families of PESs by modifying them through linear coordinate transformations based on experimental data. We demonstrate this "morphing" of the PES for the He - H2+ complex using recent comprehensive Feshbach resonance (FR) measurements for reference PESs at three different levels of quantum chemistry. In all cases, the positions and intensities of peaks in the energy distributions are improved. We find these observables to be mainly sensitive to the long-range part of the PES.
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Affiliation(s)
- Karl P. Horn
- Dahlem Center for Complex Quantum Systems and Fachbereich Physik, Freie Universität Berlin, Arnimallee 14, D-14195 Berlin, Germany
| | | | - Christiane P. Koch
- Dahlem Center for Complex Quantum Systems and Fachbereich Physik, Freie Universität Berlin, Arnimallee 14, D-14195 Berlin, Germany
| | - Markus Meuwly
- Department of Chemistry, University of Basel, Klingelbergstrasse 80, CH-4056 Basel, Switzerland
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2
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Naskar K, Ravi S, Adhikari S, Baer M, Sathyamurthy N. Beyond Born-Oppenheimer Constructed Diabatic Potential Energy Surfaces for HeH 2. J Phys Chem A 2023; 127:3832-3847. [PMID: 37098130 DOI: 10.1021/acs.jpca.3c01047] [Citation(s) in RCA: 4] [Impact Index Per Article: 4.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 05/05/2023]
Abstract
First-principles based beyond Born-Oppenheimer theory has been employed to construct multistate global Potential-Energy Surfaces (PESs) for the HeH2+ system by explicitly incorporating the Nonadiabatic Coupling Terms (NACTs). Adiabatic PESs and NACTs for the lowest four electronic states (12A', 22A', 32A' and 42A') are evaluated as functions of hyperangles for a grid of fixed values of the hyperradius in hyperspherical coordinates. Conical intersection between different states are validated by integrating the NACTs along appropriately chosen contours. Subsequently, adiabatic-to-diabatic (ADT) transformation angles are determined by solving the ADT equations to construct the diabatic potential matrix for the HeH2+ system which are smooth, single-valued, continuous, and symmetric and are suitable for performing accurate scattering calculations for the titled system.
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Affiliation(s)
- Koushik Naskar
- School of Chemical Sciences, Indian Association for the Cultivation of Science 2A & 2B Raja S. C. Mullick Road, Jadavpur, Kolkata 700032, West Bengal, India
| | - Satyam Ravi
- School of Chemical Sciences, Indian Association for the Cultivation of Science 2A & 2B Raja S. C. Mullick Road, Jadavpur, Kolkata 700032, West Bengal, India
- School of Advanced Sciences and Languages VIT Bhopal University, Bhopal, 466114, India
| | - Satrajit Adhikari
- School of Chemical Sciences, Indian Association for the Cultivation of Science 2A & 2B Raja S. C. Mullick Road, Jadavpur, Kolkata 700032, West Bengal, India
| | - Michael Baer
- The Fritz Haber Center for Molecular Dynamics, The Hebrew University of Jerusalem, Jerusalem 91904, Israel
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3
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Kędziera D, Rauhut G, Császár AG. Structure, energetics, and spectroscopy of the chromophores of HHe+n, H 2He+n, and He+n clusters and their deuterated isotopologues. Phys Chem Chem Phys 2022; 24:12176-12195. [PMID: 35543594 DOI: 10.1039/d1cp05535f] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/21/2022]
Abstract
The linear molecular ions H2He+, HHe+2, and He+3 are the central units (chromophores) of certain He-solvated complexes of the H2He+n, HHe+n, and He+n families, respectively. These are complexes which do exist, according to mass-spectrometry studies, up to very high n values. Apparently, for some of the H2He+n and He+n complexes, the linear symmetric tetratomic H2He+2 and the diatomic He+2 cations, respectively, may also be the central units. In this study, definitive structures, relative energies, zero-point vibrational energies, and (an)harmonic vibrational fundamentals, and, in some cases, overtones and combination bands, are established mostly for the triatomic chromophores. The study is also extended to the deuterated isotopologues D2He+, DHe+2, and D2He+2. To facilitate and improve the electronic-structure computations performed, new atom-centered, fixed-exponent, Gaussian-type basis sets called MAX, with X = T(3), Q(4), P(5), and H(6), are designed for the H and He atoms. The focal-point-analysis (FPA) technique is employed to determine definitive relative energies with tight uncertainties for reactions involving the molecular ions. The FPA results determined include the 0 K proton and deuteron affinities of the 4He atom, 14 875(9) cm-1 [177.95(11) kJ mol-1] and 15 229(8) cm-1 [182.18(10) kJ mol-1], respectively, the dissociation energies of the He+2 → He+ + He, HHe+2 → HHe+ + He, and He+3 → He+2 + He reactions, 19 099(13) cm-1 [228.48(16) kJ mol-1], 3948(7) cm-1 [47.23(8) kJ mol-1], and 1401(12) cm-1 [16.76(14) kJ mol-1], respectively, the dissociation energy of the DHe+2 → DHe+ + He reaction, 4033(6) cm-1 [48.25(7) kJ mol-1], the isomerization energy between the two linear isomers of the [H, He, He]+ system, 3828(40) cm-1 [45.79(48) kJ mol-1], and the dissociation energies of the H2He+ → H+2 + He and the H2He+2 → H2He+ + He reactions, 1789(4) cm-1 [21.40(5) kJ mol-1] and 435(6) cm-1 [5.20(7) kJ mol-1], respectively. The FPA estimates of the first dissociation energy of D2He+ and D2He+2 are 1986(4) cm-1 [23.76(5) kJ mol-1] and 474(5) cm-1 [5.67(6) kJ mol-1], respectively. Determining the vibrational fundamentals of the triatomic chromophores with second-order vibrational perturbation theory (VPT2) and vibrational configuration interaction (VCI) techniques, both built around the Eckart-Watson Hamiltonian, proved unusually challenging. For the species studied, VPT2 has difficulties yielding dependable results, in some cases even for the fundamentals of the H-containing molecular cations, while carefully executed VCI computations yield considerably improved spectroscopic results. In a few cases unusually large anharmonic corrections to the fundamentals, on the order of 15% of the harmonic value, have been observed.
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Affiliation(s)
- Dariusz Kędziera
- Faculty of Chemistry, Nicolaus Copernicus University in Torun, 87-100 Torun, Poland.
| | - Guntram Rauhut
- Institute for Theoretical Chemistry, University of Stuttgart, Pfaffenwaldring 55, 70569 Stuttgart, Germany.
| | - Attila G Császár
- Laboratory of Molecular Structure and Dynamics, Institute of Chemistry, ELTE Eötvös Loránd University and MTA-ELTE Complex Chemical Systems Research Group, Pázmány Péter sétány 1/A, H-1117 Budapest, Hungary.
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4
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Adhikari S, Baer M, Sathyamurthy N. HeH 2+: structure and dynamics. INT REV PHYS CHEM 2022. [DOI: 10.1080/0144235x.2022.2037883] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/18/2022]
Affiliation(s)
- Satrajit Adhikari
- School of Chemical Sciences, Indian Association for the Cultivation of Science, Jadavpur, Kolkata 700032, India
| | - Michael Baer
- The Fritz Haber Center for Molecular Dynamics, The Hebrew University of Jerusalem, Jerusalem, Israel
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5
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Koner D, Barrios L, González-Lezana T, Panda AN. Atom-Diatom Reactive Scattering Collisions in Protonated Rare Gas Systems. Molecules 2021; 26:4206. [PMID: 34299481 PMCID: PMC8304066 DOI: 10.3390/molecules26144206] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/21/2021] [Revised: 07/07/2021] [Accepted: 07/08/2021] [Indexed: 11/17/2022] Open
Abstract
The study of the dynamics of atom-diatom reactions involving two rare gas (Rg) atoms and protons is of crucial importance given the astrophysical relevance of these processes. In a series of previous studies, we have been investigating a number of such Rg(1)+ Rg(2)H+→ Rg(2)+ Rg(1)H+ reactions by means of different numerical approaches. These investigations comprised the construction of accurate potential energy surfaces by means of ab initio calculations. In this work, we review the state-of-art of the study of these protonated Rg systems making special emphasis on the most relevant features regarding the dynamical mechanisms which govern these reactive collisions. The aim of this work therefore is to provide an as complete as possible description of the existing information regarding these processes.
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Affiliation(s)
- Debasish Koner
- Department of Chemistry, Indian Institute of Science Education and Research (IISER) Tirupati, Karakambadi Road, Tirupati 517507, Andhra Pradesh, India;
| | - Lizandra Barrios
- Department of Chemistry, CMS—Centre for Molecular Simulation, IQST—Institute for Quantum Science and Technology and Quantum Alberta, University of Calgary, 2500 University Drive N.W., Calgary, AB T2N 1N4, Canada;
| | | | - Aditya N. Panda
- Department of Chemistry, Indian Institute of Technology Guwahati, Assam 781039, India;
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Montes de Oca-Estévez MJ, Prosmiti R. Computational Characterization of Astrophysical Species: The Case of Noble Gas Hydride Cations. Front Chem 2021; 9:664693. [PMID: 34046396 PMCID: PMC8144312 DOI: 10.3389/fchem.2021.664693] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/05/2021] [Accepted: 03/10/2021] [Indexed: 11/25/2022] Open
Abstract
Theoretical-computational studies together with recent astronomical observations have shown that under extreme conditions in the interstellar medium (ISM), complexes of noble gases may be formed. Such observations have generated a wide range of possibilities. In order to identify new species containing such atoms, the present study gathers spectroscopic data for noble gas hydride cations, NgH+ (Ng = He, Ne, Ar) from high-level ab initio quantum chemistry computations, aiming to contribute in understanding the chemical bonding and electron sharing in these systems. The interaction potentials are obtained from CCSD(T)/CBS and MRCI+Q calculations using large basis sets, and then employed to compute vibrational levels and molecular spectroscopic constants for all known stable isotopologues of ground state NgH+ cations. Comparisons with previously reported values available are discussed, indicating that the present data could serve as a benchmark for future studies on these systems and on higher-order cationic noble gas hydrides of astrophysical interest.
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Affiliation(s)
- María Judit Montes de Oca-Estévez
- Department of Atomic, Molecular and Surface Processes (PAMS), Institute of Fundamental Physics (IFF-CSIC), CSIC, Madrid, Spain
- Atelgraphics S.L., Madrid, Spain
| | - Rita Prosmiti
- Department of Atomic, Molecular and Surface Processes (PAMS), Institute of Fundamental Physics (IFF-CSIC), CSIC, Madrid, Spain
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7
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Koner D. Quantum and quasiclassical dynamical simulations for the Ar 2H + on a new global analytical potential energy surface. J Chem Phys 2021; 154:054303. [PMID: 33557552 DOI: 10.1063/5.0039252] [Citation(s) in RCA: 3] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/23/2023] Open
Abstract
A new analytical potential energy surface (PES) has been constructed for the Ar2H+ system from a dataset consisting of a large number of ab initio energies computed using the coupled-cluster singles, doubles and perturbative triples method and aug-cc-pVQZ basis set. The long-range interaction is added to the diatomic potentials using a standard long range expansion form to better describe the asymptotic regions. The vibrational states for the most stable structures of the Ar2H+ system have been calculated, and few low lying states are assigned to quantum numbers. Reactive scattering studies have been performed for the Ar + Ar'H+ → Ar' + ArH+ proton exchange reaction on the newly generated PES. Reaction probability, cross sections, and rate constants are calculated for the Ar + Ar'H+(v = 0, j = 0) collisions within 0.01 eV-0.6 eV of relative translational energy using exact quantum dynamical simulations as well as quasiclassical trajectory (QCT) calculations. The effect of vibrational excitation of the reactants is also explored for the reaction. State averaged rate constants are calculated for the proton exchange reaction at different temperatures using the QCT method. The mechanistic pathways for the reaction are understood by analyzing the quasiclassical trajectories.
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Affiliation(s)
- Debasish Koner
- Department of Chemistry, Indian Institute of Science Education and Research (IISER) Tirupati, Karakambadi Road, Mangalam, Tirupati 517507, Andhra Pradesh, India
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8
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Hillenbrand PM, Bowen KP, Dayou F, Miller KA, de Ruette N, Urbain X, Savin DW. Experimental study of the proton-transfer reaction C + H 2+ → CH + + H and its isotopic variant (D 2+). Phys Chem Chem Phys 2020; 22:27364-27384. [PMID: 33231243 DOI: 10.1039/d0cp04810k] [Citation(s) in RCA: 4] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/21/2022]
Abstract
We report absolute integral cross section (ICS) measurements using a dual-source merged-fast-beams apparatus to study the titular reactions over the relative translational energy range of Er ∼ 0.01-10 eV. We used photodetachment of C- to produce a pure beam of atomic C in the ground electronic 3P term, with statistically populated fine-structure levels. The H2+ and D2+ were formed in an electron impact ionization source, with well known vibrational and rotational distributions. The experimental work is complemented by a theoretical study of the CH2+ electronic system in the reactant and product channels, which helps to clarify the possible reaction mechanisms underlying the ICS measurements. Our measurements provide evidence that the reactions are barrierless and exoergic. They also indicate the apparent absence of an intermolecular isotope effect, to within the total experimental uncertainties. Capture models, taking into account either the charge-induced dipole interaction potential or the combined charge-quadrupole and charge-induced dipole interaction potentials, produce reaction cross sections that lie a factor of ∼4 above the experimental results. Based on our theoretical study, we hypothesize that the reaction is most likely to proceed adiabatically through the 14A' and 14A'' states of CH2+via the reaction C(3P) + H2+(2Σ+g) → CH+(3Π) + H(2S). We also hypothesize that at low collision energies only H2+(v ≤ 2) and D2+(v ≤ 3) contribute to the titular reactions, due to the onset of dissociative charge transfer for higher vibrational v levels. Incorporating these assumptions into the capture models brings them into better agreement with the experimental results. Still, for energies ⪅0.1 eV where capture models are most relevant, the modified charge-induced dipole model yields reaction cross sections with an incorrect energy dependence and lying ∼10% below the experimental results. The capture cross section obtained from the combined charge-quadrupole and charge-induced dipole model better matches the measured energy dependence but lies ∼30-50% above the experimental results. These findings provide important guidance for future quasiclassical trajectory and quantum mechanical treatments of this reaction.
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9
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De Fazio D, Aquilanti V, Cavalli S. Benchmark Quantum Kinetics at Low Temperatures toward Absolute Zero and Role of Entrance Channel Wells on Tunneling, Virtual States, and Resonances: The F + HD Reaction. J Phys Chem A 2020; 124:12-20. [PMID: 31829589 DOI: 10.1021/acs.jpca.9b08435] [Citation(s) in RCA: 9] [Impact Index Per Article: 2.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/28/2022]
Abstract
This paper reports a study of the quantum reaction dynamics and kinetics of the F + HD reaction at low and ultralow temperatures, focusing on the range from the Wigner limit up to 50 K. Close coupling time-independent quantum reactive scattering calculations for the production of HF and DF molecules have been carried out on two potential energy surfaces differing in the description of the reaction entrance channel. This case is computationally more demanding than the cases of F with H2 and D2 ( De Fazio et al. Frontiers in Chemistry 2019 , 7 , 328 ) but offers a wider phenomenology regarding the roles of quantum mechanical effects of tunneling, of virtual states, and of resonances. The results show that at the temperatures in the cold and ultracold regimes small changes in the entrance channel long-range interaction induce surprising near threshold features. The presence of a virtual state close to the reactive threshold gives rise to a marked anti-Arrhenius behavior of the rate constants below 100 mK. This effect enhances reaction rates by about 2 orders of magnitude, making them of the same order as those at room temperature and confining the onset of the Wigner regime in the microkelvin region.
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Affiliation(s)
- Dario De Fazio
- Istituto di Struttura della materia-Consiglio Nazionale delle Ricerche , 00016 Roma , Italy
| | - Vincenzo Aquilanti
- Istituto di Struttura della materia-Consiglio Nazionale delle Ricerche , 00016 Roma , Italy.,Dipartimento di Chimica, Biologia e Biotecnologie , Università di Perugia , 06123 Perugia , Italy
| | - Simonetta Cavalli
- Dipartimento di Chimica, Biologia e Biotecnologie , Università di Perugia , 06123 Perugia , Italy
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10
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González-Lezana T, Bossion D, Scribano Y, Bhowmick S, Suleimanov YV. Dynamics of H + HeH +( v = 0, j = 0) → H 2+ + He: Insight on the Possible Complex-Forming Behavior of the Reaction. J Phys Chem A 2019; 123:10480-10489. [PMID: 31725286 DOI: 10.1021/acs.jpca.9b06122] [Citation(s) in RCA: 6] [Impact Index Per Article: 1.2] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/29/2022]
Abstract
The H + HeH+→ He + H2+ reaction has been studied by means of a combination of theoretical approaches: a statistical quantum method (SQM), ring polymer molecular dynamics (RPMD), and the quasiclassical trajectory (QCT) method. Cross sections and rate constants have been calculated in an attempt to investigate the dynamics of the process. The comparison with previous calculations and experimental results reveals that despite the fact that statistical predictions seem to reproduce some of the overall observed features, the analysis at a more detailed state-to-state level shows noticeable deviations from a complex-forming dynamics. We find some differences in cross sections and rate constants obtained in the QCT calculation with a Gaussian binning procedure with respect to previous works in which the standard histogram binning was employed.
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Affiliation(s)
| | - Duncan Bossion
- Laboratoire Univers et Particules de Montpellier, UMR-CNRS 5299 , Université de Montpellier , 34095 Montpellier Cedex , France
| | - Yohann Scribano
- Laboratoire Univers et Particules de Montpellier, UMR-CNRS 5299 , Université de Montpellier , 34095 Montpellier Cedex , France
| | - Somnath Bhowmick
- Computation-based Science and Technology Research Center , The Cyprus Institute , 20 Konstantinou Kavafi Street , Nicosia 2121 , Cyprus
| | - Yury V Suleimanov
- Computation-based Science and Technology Research Center , The Cyprus Institute , 20 Konstantinou Kavafi Street , Nicosia 2121 , Cyprus
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11
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Császár AG, Szidarovszky T, Asvany O, Schlemmer S. Fingerprints of microscopic superfluidity in HHe n+ clusters. Mol Phys 2019. [DOI: 10.1080/00268976.2019.1585984] [Citation(s) in RCA: 7] [Impact Index Per Article: 1.4] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/27/2022]
Affiliation(s)
- Attila G. Császár
- Laboratory of Molecular Structure and Dynamics, Institute of Chemistry, ELTE Eötvös Loránd University and MTA-ELTE Complex Chemical Systems Research Group, Budapest, Hungary
| | - Tamás Szidarovszky
- Laboratory of Molecular Structure and Dynamics, Institute of Chemistry, ELTE Eötvös Loránd University and MTA-ELTE Complex Chemical Systems Research Group, Budapest, Hungary
| | - Oskar Asvany
- I. Physikalisches Institut, Universität zu Köln, Köln, Germany
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12
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De Fazio D, Aguado A, Petrongolo C. Non-adiabatic Quantum Dynamics of the Dissociative Charge Transfer He ++H 2 → He+H+H . Front Chem 2019; 7:249. [PMID: 31041310 PMCID: PMC6477054 DOI: 10.3389/fchem.2019.00249] [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: 02/08/2019] [Accepted: 03/27/2019] [Indexed: 11/27/2022] Open
Abstract
We present the non-adiabatic, conical-intersection quantum dynamics of the title collision where reactants and products are in the ground electronic states. Initial-state-resolved reaction probabilities, total integral cross sections, and rate constants of two H2 vibrational states, v0 = 0 and 1, in the ground rotational state (j0 = 0) are obtained at collision energies Ecoll ≤ 3 eV. We employ the lowest two excited diabatic electronic states of HeH2+ and their electronic coupling, a coupled-channel time-dependent real wavepacket method, and a flux analysis. Both probabilities and cross sections present a few groups of resonances at low Ecoll, whose amplitudes decrease with the energy, due to an ion-induced dipole interaction in the entrance channel. At higher Ecoll, reaction probabilities and cross sections increase monotonically up to 3 eV, remaining however quite small. When H2 is in the v0 = 1 state, the reactivity increases by ~2 orders of magnitude at the lowest energies and by ~1 order at the highest ones. Initial-state resolved rate constants at room temperature are equal to 1.74 × 10−14 and to 1.98 × 10−12 cm3s−1 at v0 = 0 and 1, respectively. Test calculations for H2 at j0 = 1 show that the probabilities can be enhanced by a factor of ~1/3, that is ortho-H2 seems ~4 times more reactive than para-H2.
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Affiliation(s)
- Dario De Fazio
- Consiglio Nazionale delle Ricerche, Istituto di Struttura della Materia, Rome, Italy
| | - Alfredo Aguado
- Departamento de Química Física Aplicada, Facultad de Ciencias, Universidad Autónoma de Madrid, Madrid, Spain
| | - Carlo Petrongolo
- Consiglio Nazionale delle Ricerche, Istituto per i Processi Chimico Fisici, Pisa, Italy
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13
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Salomon T, Töpfer M, Schreier P, Schlemmer S, Kohguchi H, Surin L, Asvany O. Double resonance rotational spectroscopy of He-HCO . Phys Chem Chem Phys 2019; 21:3440-3445. [PMID: 30191208 DOI: 10.1039/c8cp04532a] [Citation(s) in RCA: 16] [Impact Index Per Article: 3.2] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/21/2022]
Abstract
The ground state of He-HCO+ is investigated using a recently developed double resonance technique, consisting of a rotational transition followed by a vibrational transition into a dissociative state. In order to derive precise predictions for the rotational states, the high resolution infrared predissociation spectroscopy of the v1 C-H stretching mode is revisited. Eleven pure rotational transitions are measured via the double resonance method. A least squares fit of these transitions to a standard linear rotor Hamiltonian reveals that the semirigid rotor model cannot fully describe the loosely bound He-HCO+ complex. The novel double resonance technique is compared with other action spectroscopic schemes, and some potential future applications are presented.
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Affiliation(s)
- Thomas Salomon
- I. Physikalisches Institut, Universität zu Köln, Zülpicher Str. 77, 50937 Köln, Germany.
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14
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Koner D, San Vicente Veliz JC, van der Avoird A, Meuwly M. Near dissociation states for H2+–He on MRCI and FCI potential energy surfaces. Phys Chem Chem Phys 2019; 21:24976-24983. [DOI: 10.1039/c9cp05259c] [Citation(s) in RCA: 19] [Impact Index Per Article: 3.8] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/21/2022]
Abstract
Ro-vibrational states for H2+–He on new kernel-based potential energy surfaces based on MRCI and FCI calculations.
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Affiliation(s)
- Debasish Koner
- Department of Chemistry
- University of Basel
- CH-4056 Basel
- Switzerland
| | | | - Ad van der Avoird
- Theoretical Chemistry
- Institute for Molecules and Materials
- Radboud University Nijmegen
- Nijmegen
- The Netherlands
| | - Markus Meuwly
- Department of Chemistry
- University of Basel
- CH-4056 Basel
- Switzerland
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15
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He X, Li W, Meng H, Li C, Guo G, Qiu X, Wei J. Quantum state-to-state study for (H−(D−),HD) collisions on two potential energy surfaces. Phys Chem Chem Phys 2019; 21:7196-7207. [DOI: 10.1039/c8cp07824f] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.4] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/01/2023]
Abstract
Revealing the reaction mechanisms of the H−/D− + HD reaction – an exact quantum dynamics study on two potential energy surfaces.
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Affiliation(s)
- Xiaohu He
- Department of Physics
- Taiyuan University of Science and Technology
- Taiyuan
- China
| | - Wenliang Li
- Department of Physics
- Xinjiang Institute of Engineering
- Urumqi
- China
| | - Huiyan Meng
- Department of Physics
- Taiyuan University of Science and Technology
- Taiyuan
- China
| | - Chuanliang Li
- Department of Physics
- Taiyuan University of Science and Technology
- Taiyuan
- China
| | - Guqing Guo
- Department of Physics
- Taiyuan University of Science and Technology
- Taiyuan
- China
| | - Xuanbing Qiu
- Department of Physics
- Taiyuan University of Science and Technology
- Taiyuan
- China
| | - Jilin Wei
- Department of Physics
- Taiyuan University of Science and Technology
- Taiyuan
- China
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16
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Papp D, Szidarovszky T, Császár AG. A general variational approach for computing rovibrational resonances of polyatomic molecules. Application to the weakly bound H 2He + and H 2⋅CO systems. J Chem Phys 2018; 147:094106. [PMID: 28886650 DOI: 10.1063/1.5000680] [Citation(s) in RCA: 13] [Impact Index Per Article: 2.2] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/14/2022] Open
Abstract
The quasi-variational quantum chemical protocol and code GENIUSH [E. Mátyus et al., J. Chem. Phys. 130, 134112 (2009) and C. Fábri et al., J. Chem. Phys. 134, 074105 (2011)] has been augmented with the complex absorbing potential (CAP) technique, yielding a method for the determination of rovibrational resonance states. Due to the effective implementation of the CAP technique within GENIUSH, the GENIUSH-CAP code is a powerful tool for the study of important dynamical features of arbitrary-sized molecular systems with arbitrary composition above their first dissociation limit. The GENIUSH-CAP code has been tested and validated on the H2He+ cation: the computed resonance energies and lifetimes are compared to those obtained with a previously developed triatomic rovibrational resonance-computing code, D2FOPI-CCS [T. Szidarovszky and A. G. Császár Mol. Phys. 111, 2131 (2013)], utilizing the complex coordinate scaling method. A unique feature of the GENIUSH-CAP protocol is that it allows the simple implementation of reduced-dimensional dynamical models. To prove this, resonance energies and lifetimes of the H2⋅CO van der Waals complex have been computed utilizing a four-dimensional model (freezing the two monomer stretches), and a related potential energy surface, of the complex.
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Affiliation(s)
- Dóra Papp
- Laboratory of Molecular Structure and Dynamics, Institute of Chemistry, Eötvös Loránd University and MTA-ELTE Complex Chemical Systems Research Group, Pázmány Péter sétány 1/A, H-1117 Budapest, Hungary
| | - Tamás Szidarovszky
- Laboratory of Molecular Structure and Dynamics, Institute of Chemistry, Eötvös Loránd University and MTA-ELTE Complex Chemical Systems Research Group, Pázmány Péter sétány 1/A, H-1117 Budapest, Hungary
| | - Attila G Császár
- Laboratory of Molecular Structure and Dynamics, Institute of Chemistry, Eötvös Loránd University and MTA-ELTE Complex Chemical Systems Research Group, Pázmány Péter sétány 1/A, H-1117 Budapest, Hungary
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17
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Papp D, Császár AG, Yamanouchi K, Szidarovszky T. Rovibrational Resonances in H 2He . J Chem Theory Comput 2018; 14:1523-1533. [PMID: 29390185 DOI: 10.1021/acs.jctc.7b01136] [Citation(s) in RCA: 13] [Impact Index Per Article: 2.2] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/29/2022]
Abstract
The nuclear dynamics of the metastable H2He+ complex is explored by symmetry considerations and angular momentum addition rules as well as by accurate quantum chemical computations with complex coordinate scaling, complex absorbing potential, and stabilization techniques. About 200 long-lived rovibrational resonance states of the complex are characterized and selected long-lived states are analyzed in detail. The stabilization mechanism of these long-lived resonance states is discussed on the basis of probability density plots of the wave functions. Overlaps of wave functions derived by a reduced-dimensional model with the full-dimensional wave functions reveal dissociation pathways for the long-lived resonance states and allow the calculation of their branching ratios.
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Affiliation(s)
- Dóra Papp
- Laboratory of Molecular Structure and Dynamics, Institute of Chemistry , Eötvös Loránd University and MTA-ELTE Complex Chemical Systems Research Group , Pázmány Péter sétány 1/A , H-1117 Budapest , Hungary
| | - Attila G Császár
- Laboratory of Molecular Structure and Dynamics, Institute of Chemistry , Eötvös Loránd University and MTA-ELTE Complex Chemical Systems Research Group , Pázmány Péter sétány 1/A , H-1117 Budapest , Hungary
| | - Kaoru Yamanouchi
- The University of Tokyo , 7-3-1 Hongo , Bunkyo-ku, Tokyo 113-0033 , Japan
| | - Tamás Szidarovszky
- Laboratory of Molecular Structure and Dynamics, Institute of Chemistry , Eötvös Loránd University and MTA-ELTE Complex Chemical Systems Research Group , Pázmány Péter sétány 1/A , H-1117 Budapest , Hungary
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18
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Vila HVR, Ribeiro LA, Macedo LGMD, Gargano R. On the Angular Distribution of the H+Li 2 Cross Sections: a Converged Time-Independent Quantum Scattering Study. Sci Rep 2018; 8:1044. [PMID: 29348595 PMCID: PMC5773505 DOI: 10.1038/s41598-018-19233-0] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/10/2017] [Accepted: 12/21/2017] [Indexed: 11/17/2022] Open
Abstract
A thorough time-independent quantum scattering study is performed on a benchmark potential energy surface for the H+Li2 reaction at the fundamental electronic state. Integral and differential cross sections are calculated along with thermal rate coefficients until convergence is reached. Our findings show that vibrational and rotational excitations of the reactant hinder reactivity, though for the latter a considerable reaction promotion was spotted as we increase the reactant rotational quantum number until the critical value of j = 4. Such a promotion then begins to retract, eventually becoming an actual inhibition for larger j. In a straightforward manner, the concept of time-independent methods implemented in this study allowed this accurate state-to-state analysis. Furthermore, a nearly isotropic behaviour of the scattering is noted to take place from the angular point of view. Remarkably, our computational protocol is ideally suited to yield converged thermal rate coefficients, revealing a non-Arrhenius pattern and showing that J-shifting approach fails to describe this particular reaction. Our results, when compared to previous and independent ones, reinforce the latest theoretical reference for future validation in the experimental field.
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Affiliation(s)
| | - Luiz Antônio Ribeiro
- International Center for Condensed Matter Physics, University of Brasília, P. O. Box 04531, 70.919-970, Brasília, Brazil.,Department of Physics, Chemistry and Biology (IFM), Linköping University, SE-581 83, Linköping, Sweden
| | | | - Ricardo Gargano
- Institute of Physics, University of Brasília, P. O. Box 04455, 70.919-970, Brasília-DF, Brazil.
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19
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Hernández Vera M, Gianturco FA, Wester R, da Silva H, Dulieu O, Schiller S. Rotationally inelastic collisions of H2+ ions with He buffer gas: Computing cross sections and rates. J Chem Phys 2017; 146:124310. [PMID: 28388146 DOI: 10.1063/1.4978475] [Citation(s) in RCA: 19] [Impact Index Per Article: 2.7] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/14/2022] Open
Affiliation(s)
- Mario Hernández Vera
- Institut für Ionenphysik und Angewandte Physik, Universität Innsbruck, Technikerstr. 25/3, A-6020 Innsbruck, Austria
| | - F. A. Gianturco
- Institut für Ionenphysik und Angewandte Physik, Universität Innsbruck, Technikerstr. 25/3, A-6020 Innsbruck, Austria
| | - R. Wester
- Institut für Ionenphysik und Angewandte Physik, Universität Innsbruck, Technikerstr. 25/3, A-6020 Innsbruck, Austria
| | - H. da Silva
- Laboratoire Aimé Cotton, CNRS, Université Paris-Sud, ENS Paris-Saclay, Université Paris-Saclay, Orsay, France
| | - O. Dulieu
- Laboratoire Aimé Cotton, CNRS, Université Paris-Sud, ENS Paris-Saclay, Université Paris-Saclay, Orsay, France
| | - S. Schiller
- Institut für Experimentalphysik, Heinrich-Heine-Universität Düsseldorf, Universtätsstr. 1, D-40225 Düsseldorf, Germany
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20
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Szidarovszky T, Yamanouchi K. Full-dimensional simulation of the laser-induced alignment dynamics of H2He+. Mol Phys 2017. [DOI: 10.1080/00268976.2017.1297863] [Citation(s) in RCA: 6] [Impact Index Per Article: 0.9] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/19/2022]
Affiliation(s)
- Tamás Szidarovszky
- Department of Chemistry, School of Science, The University of Tokyo , Tokyo, Japan
| | - Kaoru Yamanouchi
- Department of Chemistry, School of Science, The University of Tokyo , Tokyo, Japan
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21
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Koner D, Barrios L, González-Lezana T, Panda AN. Scattering study of the Ne + NeH(+)(v0 = 0, j0 = 0) → NeH(+) + Ne reaction on an ab initio based analytical potential energy surface. J Chem Phys 2016; 144:034303. [PMID: 26801030 DOI: 10.1063/1.4939952] [Citation(s) in RCA: 15] [Impact Index Per Article: 1.9] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/14/2022] Open
Abstract
Initial state selected dynamics of the Ne + NeH(+)(v0 = 0, j0 = 0) → NeH(+) + Ne reaction is investigated by quantum and statistical quantum mechanical (SQM) methods on the ground electronic state. The three-body ab initio energies on a set of suitably chosen grid points have been computed at CCSD(T)/aug-cc-PVQZ level and analytically fitted. The fitting of the diatomic potentials, computed at the same level of theory, is performed by spline interpolation. A collinear [NeHNe](+) structure lying 0.72 eV below the Ne + NeH(+) asymptote is found to be the most stable geometry for this system. Energies of low lying vibrational states have been computed for this stable complex. Reaction probabilities obtained from quantum calculations exhibit dense oscillatory structures, particularly in the low energy region and these get partially washed out in the integral cross section results. SQM predictions are devoid of oscillatory structures and remain close to 0.5 after the rise at the threshold thus giving a crude average description of the quantum probabilities. Statistical cross sections and rate constants are nevertheless in sufficiently good agreement with the quantum results to suggest an important role of a complex-forming dynamics for the title reaction.
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Affiliation(s)
- Debasish Koner
- Department of Chemistry, Indian Institute of Technology Guwahati, Guwahati 781039, India
| | - Lizandra Barrios
- IFF-CSIC, Instituto de Física Fundamental, CSIC, Serrano 123, Madrid 28006, Spain
| | | | - Aditya N Panda
- Department of Chemistry, Indian Institute of Technology Guwahati, Guwahati 781039, India
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22
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De Fazio D, Cavalli S, Aquilanti V. Benchmark Quantum Mechanical Calculations of Vibrationally Resolved Cross Sections and Rate Constants on ab Initio Potential Energy Surfaces for the F + HD Reaction: Comparisons with Experiments. J Phys Chem A 2016; 120:5288-99. [PMID: 27186680 DOI: 10.1021/acs.jpca.6b01471] [Citation(s) in RCA: 9] [Impact Index Per Article: 1.1] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/29/2022]
Affiliation(s)
- Dario De Fazio
- Istituto di Struttura della
Materia, Consiglio Nazionale delle Ricerche, 00016 Roma, Italy
| | - Simonetta Cavalli
- Dipartimento di Chimica,
Biologia e Biotecnologie, Università di Perugia, 06123 Perugia, Italy
| | - Vincenzo Aquilanti
- Dipartimento di Chimica,
Biologia e Biotecnologie, Università di Perugia, 06123 Perugia, Italy
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23
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Freixas-Lemus VM, Martínez-Mesa A, Uranga-Piña L. Quasi-Classical Trajectory Study of Atom-Diatomic Molecule Collisions in Symmetric Hyperspherical Coordinates: The F + HCl Reaction as a Test Case. J Phys Chem A 2016; 120:2059-69. [PMID: 27002240 DOI: 10.1021/acs.jpca.5b11525] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.1] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/28/2022]
Abstract
We investigate the reactive dynamics of the triatomic system F + HCl → HF + Cl for total angular momentum equal zero and for different low-lying rovibrational states of the diatomic molecule. For each of the initial vibrational quantum numbers, the time evolution of the atom-diatom collision process is investigated for a wide range of impact angles and collision energies. To this purpose, the Quasi-Classical Trajectories (QCT) method was implemented in a hyperspherical configuration space. The Hamilton equations of motion are solved numerically in an intermediate effective Cartesian space to exploit the relative simplicity of this intermediate representation. Interatomic interactions are described by a London-Eyring-Polanyi-Sato potential energy surface, specifically developed for the title reaction, and the results of the QCT simulations are discussed in terms of the time-evolution of the hyperangles. The analysis of the collision dynamics using symmetric hyperspherical coordinates provides, in addition to the description in terms of a natural reaction coordinate (the hyperradius), a more striking representation of the exchange dynamics, in terms of the time-dependent probability distribution along the kinematic rotation hyperangle, and a precise distinction between direct and indirect mechanisms of the reaction.
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Affiliation(s)
- Victor Manuel Freixas-Lemus
- DynAMoS (Dynamical processes in Atomic and Molecular Systems), Facultad de Física, Universidad de la Habana , San Lázaro y L, La Habana 10400, Cuba
| | - Aliezer Martínez-Mesa
- DynAMoS (Dynamical processes in Atomic and Molecular Systems), Facultad de Física, Universidad de la Habana , San Lázaro y L, La Habana 10400, Cuba
| | - Llinersy Uranga-Piña
- DynAMoS (Dynamical processes in Atomic and Molecular Systems), Facultad de Física, Universidad de la Habana , San Lázaro y L, La Habana 10400, Cuba
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24
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Koner D, Barrios L, González-Lezana T, Panda AN. State-to-State Dynamics of the Ne + HeH(+) (v = 0, j = 0) → NeH(+)(v', j') + He Reaction. J Phys Chem A 2016; 120:4731-41. [PMID: 26943458 DOI: 10.1021/acs.jpca.5b11477] [Citation(s) in RCA: 14] [Impact Index Per Article: 1.8] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/28/2022]
Abstract
The dynamics of the Ne + HeH(+)(v = 0, j = 0) → NeH(+)(v', j') + He reaction was analyzed in detail at the state-to-state level. A time-independent quantum mechanical (TIQM) method was applied to calculate rovibrational distributions and differential cross sections (DCSs), in comparison with quasi-classical trajectory and statistical quantum predictions. Possible changes in the dynamical mechanisms that define the process were also investigated as a function of the collision energy. At the lowest energy regime, the TIQM results produce a noticeably different cross section in comparison with previously reported time-dependent wave packet results. Although the statistical methods reproduce some dynamical features, especially as the energy increases, the marked preference for the forward scattering direction on the DCSs suggests that the reaction mainly follows a direct mechanism.
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Affiliation(s)
- Debasish Koner
- Department of Chemistry, Indian Institute of Technology , Guwahati 781039, India
| | - Lizandra Barrios
- Instituto de Física Fundamental, IFF-CSIC , Serrano 123, Madrid 28006, Spain
| | | | - Aditya N Panda
- Department of Chemistry, Indian Institute of Technology , Guwahati 781039, India
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25
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Esposito F, Coppola CM, De Fazio D. Complementarity between Quantum and Classical Mechanics in Chemical Modeling. The H + HeH+ → H2 + + He Reaction: A Rigourous Test for Reaction Dynamics Methods. J Phys Chem A 2015; 119:12615-26. [PMID: 26583384 DOI: 10.1021/acs.jpca.5b09660] [Citation(s) in RCA: 12] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/30/2022]
Abstract
In this work we present a dynamical study of the H + HeH+ → H2+ + He reaction in a collision energy range from 0.1 meV to 10 eV, suitable to be used in applicative models. The paper extends and complements a recent work [ Phys. Chem. Chem. Phys. 2014, 16, 11662] devoted to the characterization of the reactivity from the ultracold regime up to the three-body dissociation breakup. In particular, the accuracy of the quasi-classical trajectory method below the three-body dissociation threshold has been assessed by a detailed comparison with previous calculations performed with different reaction dynamics methods, whereas the reliability of the results in the high energy range has been checked by a direct comparison with the available experimental data. Integral cross sections for several HeH+ roto-vibrational states have been analyzed and used to understand the extent of quantum effects in the reaction dynamics. By using the quasi-classical trajectory method and quantum mechanical close coupling data, respectively, in the high and low collision energy ranges, we obtain highly accurate thermal rate costants until 15 000 K including all (178) the roto-vibrational bound and quasi-bound states of HeH+. The role of the collision-induced dissociation is also discussed and explicitly calculated for the ground roto-vibrational state of HeH+.
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Affiliation(s)
- Fabrizio Esposito
- Consiglio Nazionale delle Ricerche, Istituto di Nanotecnologia, via Amendola 122/d, 70126 Bari, Italy
| | - Carla Maria Coppola
- Consiglio Nazionale delle Ricerche, Istituto di Nanotecnologia, via Amendola 122/d, 70126 Bari, Italy.,INAF-Osservatorio Astrofisico di Arcetri , 50125 Firenze, Italy
| | - Dario De Fazio
- Consiglio Nazionale delle Ricerche, Istituto di Struttura della Materia, Area della Ricerca di Roma 1, 00016 Roma, Italy
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26
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Larrégaray P, Bonnet L. Quantum state-resolved differential cross sections for complex-forming chemical reactions: Asymmetry is the rule, symmetry the exception. J Chem Phys 2015; 143:144113. [DOI: 10.1063/1.4933009] [Citation(s) in RCA: 9] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/14/2022] Open
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27
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Koner D, Barrios L, González-Lezana T, Panda AN. Quantum, Statistical, and Quasiclassical Trajectory Studies For the Ne + HeH(+) → NeH(+) + He Reaction on the Ground Electronic State. J Phys Chem A 2015; 119:12052-61. [PMID: 26172109 DOI: 10.1021/acs.jpca.5b04830] [Citation(s) in RCA: 9] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/29/2022]
Abstract
Real wave packet, statistical quantum, and quasiclassical trajectory methods were employed to study the dynamics of Ne + HeH(+)(v0,j0) → He + NeH(+) reaction on an ab initio potential energy surface [J. Phys. Chem. A 2013, 117, 13070-13078]. Quantum and statistical quantum calculations were performed within the centrifugal sudden (CS) approximation as well as including the Coriolis coupling (CC). Dense oscillatory structures of the quantum reaction probabilities and fair agreement between quantum and statistical cross sections suggest a complex forming mechanism for the reaction. No significant differences between cross sections obtained within the CS and CC approaches are observed. Quasiclassical trajectory results give an excellent average description of the quantum CC results. At low collision energies, there is a substantial decrease in reactivity for the reaction upon rovibrational excitation. Initial state selected rate constants for the title reaction are calculated between 20 and 1000 K, and the calculated value at 300 K agrees quite well with the available experimental result. Reaction cross sections and rate constants are also compared with those calculated via the Langevin capture model for exothermic reactions.
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Affiliation(s)
- Debasish Koner
- Department of Chemistry, Indian Institute of Technology Guwahati, Assam 781039, India
| | - Lizandra Barrios
- Instituto de Física Fundamental, C.S.I.C. , Serrano 123, Madrid 28006, Spain
| | | | - Aditya N Panda
- Department of Chemistry, Indian Institute of Technology Guwahati, Assam 781039, India
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28
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Koner D, Barrios L, González-Lezana T, Panda AN. Wave packet and statistical quantum calculations for the He + NeH⁺ → HeH⁺ + Ne reaction on the ground electronic state. J Chem Phys 2015; 141:114302. [PMID: 25240353 DOI: 10.1063/1.4895567] [Citation(s) in RCA: 15] [Impact Index Per Article: 1.7] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/14/2022] Open
Abstract
A real wave packet based time-dependent method and a statistical quantum method have been used to study the He + NeH(+) (v, j) reaction with the reactant in various ro-vibrational states, on a recently calculated ab initio ground state potential energy surface. Both the wave packet and statistical quantum calculations were carried out within the centrifugal sudden approximation as well as using the exact Hamiltonian. Quantum reaction probabilities exhibit dense oscillatory pattern for smaller total angular momentum values, which is a signature of resonances in a complex forming mechanism for the title reaction. Significant differences, found between exact and approximate quantum reaction cross sections, highlight the importance of inclusion of Coriolis coupling in the calculations. Statistical results are in fairly good agreement with the exact quantum results, for ground ro-vibrational states of the reactant. Vibrational excitation greatly enhances the reaction cross sections, whereas rotational excitation has relatively small effect on the reaction. The nature of the reaction cross section curves is dependent on the initial vibrational state of the reactant and is typical of a late barrier type potential energy profile.
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Affiliation(s)
- Debasish Koner
- Department of Chemistry, Indian Institute of Technology Guwahati, Guwahati 781039, India
| | - Lizandra Barrios
- Instituto de Física Fundamental, C.S.I.C., Serrano 123, Madrid 28006, Spain
| | | | - Aditya N Panda
- Department of Chemistry, Indian Institute of Technology Guwahati, Guwahati 781039, India
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29
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De Fazio D. The H + HeH(+) → He + H2(+) reaction from the ultra-cold regime to the three-body breakup: exact quantum mechanical integral cross sections and rate constants. Phys Chem Chem Phys 2015; 16:11662-72. [PMID: 24810283 DOI: 10.1039/c4cp00502c] [Citation(s) in RCA: 36] [Impact Index Per Article: 4.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/21/2022]
Abstract
In this work, we present a quantum mechanical scattering study of the title reaction from 1 mK to 2000 K. Total integral cross sections and thermal rate constants are compared with previous theoretical and experimental data and with simpler theoretical models to understand the range of validity of the approximations used in the previous studies. The obtained quantum reactive observables have been found to be nearly insensitive to the roto-vibrational energy of the reactants at high temperatures. More sensitive to the reactant's roto-vibrational energy are the data in the cold and ultra-cold regimes. The implications of the new data presented here in the early universe scenario are also discussed and analyzed.
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Affiliation(s)
- Dario De Fazio
- Istituto di Struttura della Materia - C.N.R., 00016 Roma, Italy.
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30
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Sokolovski D, Akhmatskaya E, Echeverría-Arrondo C, De Fazio D. Complex angular momentum theory of state-to-state integral cross sections: resonance effects in the F + HD → HF(v′ = 3) + D reaction. Phys Chem Chem Phys 2015; 17:18577-89. [DOI: 10.1039/c5cp01169h] [Citation(s) in RCA: 11] [Impact Index Per Article: 1.2] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/21/2022]
Abstract
State-to-state reactive integral cross sections (ICSs) are often affected by quantum mechanical resonances, especially in the neighborhood of a reactive threshold.
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Affiliation(s)
- D. Sokolovski
- Departmento de Química-Física
- Universidad del País Vasco
- UPV/EHU
- Leioa
- Spain
| | - E. Akhmatskaya
- IKERBASQUE
- Basque Foundation for Science
- Bilbao
- Spain
- Basque Center for Applied Mathematics (BCAM)
| | | | - D. De Fazio
- Istituto di Struttura della Materia
- CNR
- 00016 Roma
- Italy
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31
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González-Lezana T, Scribano Y, Honvault P. The D(+) + H2 reaction: differential and integral cross sections at low energy and rate constants at low temperature. J Phys Chem A 2014; 118:6416-24. [PMID: 24802076 DOI: 10.1021/jp501446y] [Citation(s) in RCA: 15] [Impact Index Per Article: 1.5] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/14/2022]
Abstract
The D(+) + H2 reaction is investigated by means of a time independent quantum mechanical (TIQM) and statistical quantum mechanical (SQM) methods. Differential cross sections and product rotational distributions obtained with these two theoretical approaches for collision energies between 1 meV and 0.1 eV are compared to analyze the dynamics of the process. The agreement observed between the TIQM differential cross sections and the SQM predictions as the energy increases revealed the role played by the complex-forming mechanism. The importance of a good description of the asymptotic regions is also investigated by calculating rate constants for the title reaction at low temperature.
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32
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Gamallo P, Akpinar S, Defazio P, Petrongolo C. Quantum Dynamics of the Reaction H(2S) + HeH+(X1Σ+) → H2+(X2Σg+) + He(1S) from Cold to Hyperthermal Energies: Time-Dependent Wavepacket Study and Comparison with Time-Independent Calculations. J Phys Chem A 2014; 118:6451-6. [DOI: 10.1021/jp5023289] [Citation(s) in RCA: 11] [Impact Index Per Article: 1.1] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/29/2022]
Affiliation(s)
- Pablo Gamallo
- Departament
de Quı́mica Fı́sica, Institut
de Quı́mica Teòrica i Computacional, Universitat de Barcelona, C/Martı́ i Franquès 1, 08028 Barcelona, Spain
| | - Sinan Akpinar
- Department
of Physics, Firat University, 23169 Elazig, Turkey
| | - Paolo Defazio
- Dipartimento
di Biotecnologie, Chimica, e Farmacia, Università di Siena, Via A. Moro
2, 53100 Siena, Italy
| | - Carlo Petrongolo
- Istituto per i
Processi Chimico-Fisici, Consiglio Nazionale delle Ricerche, Via G. Moruzzi 1, 56124 Pisa, Italy
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33
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Krasilnikov MB, Popov RS, Roncero O, De Fazio D, Cavalli S, Aquilanti V, Vasyutinskii OS. Polarization of molecular angular momentum in the chemical reactions Li + HF and F + HD. J Chem Phys 2013; 138:244302. [DOI: 10.1063/1.4809992] [Citation(s) in RCA: 7] [Impact Index Per Article: 0.6] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/17/2022] Open
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