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Loreau J, van der Avoird A. Vibrational energy transfer in ammonia-helium collisions. Faraday Discuss 2024. [PMID: 38787637 DOI: 10.1039/d3fd00180f] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 05/26/2024]
Abstract
While the rotational energy transfer of ammonia by rare gas atoms and hydrogen molecules has been the focus of many studies, little is known about its vibrational relaxation, even though transitions involving the umbrella bending mode have been observed in many astrophysical environments. Here we explore the vibrational relaxation of the umbrella mode of ammonia induced by collisions with helium atoms by means of the close-coupling method on an ab initio potential energy surface. We compute cross sections up to kinetic energies of 1500 cm-1 and rate coefficients up to a temperature of 300 K for vibrational, rotational, and inversion transitions involving the lowest two vibrational states. We show that vibrational relaxation is much less efficient than rotation-inversion relaxation, although the rate coefficients for vibrational relaxation strongly increase with the temperature. We also observe important differences for vibrationally-elastic transitions within the lowest two vibrational states, i.e., for rotation-inversion transitions. These are a direct consequence of the difference in the tunnelling splitting of the lowest inversion levels.
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Affiliation(s)
- Jérôme Loreau
- KU Leuven, Department of Chemistry, B-3001 Leuven, Belgium.
| | - Ad van der Avoird
- Institute for Molecules and Materials, Radboud University, Heyendaalseweg 135, 6525 AJ Nijmegen, The Netherlands
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2
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Ben Khalifa M, Dagdigian PJ, Loreau J. Interaction of CH 3CN and CH 3NC with He: Potential Energy Surfaces and Low-Energy Scattering. J Phys Chem A 2022; 126:9658-9666. [PMID: 36534035 DOI: 10.1021/acs.jpca.2c06925] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/23/2022]
Abstract
Several nitrogen-bearing molecules, such as methyl cyanide (or acetonitrile, CH3CN) and methyl isocyanide (CH3NC) of interest here, have been observed in various astrophysical environments. The accurate modeling of their abundance requires the calculation of rate coefficients for their collisional excitation with species such as He atoms or H2 molecules at low temperatures. In this work we compute new three-dimensional potential energy surfaces for the CH3NC-He and CH3CN-He van der Waals complexes by means of the explicitly correlated coupled cluster approach with single, double and perturbative triple excitation CCSD(T)/F12a in conjunction with the aug-cc-pVTZ basis set. We find a global minimum with De = 55.10 and 58.61 cm-1 for CH3CN-He and CH3NC-He, respectively, while the dissociation energy D0 of the complexes are 18.64 and 18.65 cm-1, respectively. Low-energy scattering calculations of pure rotational (de-)excitation of CH3CN and CH3NC by collision with He atoms are carried out with the close-coupling method, and the collisional cross sections of ortho- and para-CH3NC and CH3CN are computed for kinetic energies up to 100 cm-1. While the PESs for both complexes are qualitatively similar, that of CH3NC-He is more anisotropic, leading to different propensity rules for rotational excitation. For CH3NC-He, we find that |Δj| = 1 transitions are dominant at low kinetic energy and a propensity rule that favors odd Δj transitions is observed, whereas for CH3CN the dominant cross sections are associated with transitions with |Δj| = 2. We expect that the findings of this study will be beneficial for astrophysical investigations as well as laboratory experiments.
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Affiliation(s)
- Malek Ben Khalifa
- KU Leuven, Department of Chemistry, Celestijnenlaan 200F, B-3001Leuven, Belgium
| | - Paul J Dagdigian
- The Johns Hopkins University, Department of Chemistry, Baltimore, Maryland21218-2685, United States
| | - Jérôme Loreau
- KU Leuven, Department of Chemistry, Celestijnenlaan 200F, B-3001Leuven, Belgium
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3
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Palazzetti F, Cappelletti D, Coletti C, Falcinelli S, Pirani F. Molecular beam scattering experiments on noble gas-propylene oxide: Total integral cross sections and potential energy surfaces of He- and Ne-C 3H 6O. J Chem Phys 2021; 155:234301. [PMID: 34937350 DOI: 10.1063/5.0073737] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/04/2023] Open
Abstract
The interactions of He and Ne with propylene oxide have been investigated with the molecular beam technique by measuring the total (elastic + inelastic) integral cross section as a function of collision velocity. Starting from the analysis of these experimental data, potential energy surfaces, formulated as a function of the separation distance and orientation of propylene oxide with respect to the interacting partners, have been built: The average depth of potential wells (located at intermediate separation distances) has been characterized by analyzing the observed "glory" quantum effects, and the strength of long-range attractions has been obtained from the magnitude and the velocity dependence of the smooth component of measured cross sections. The surfaces, tested and improved against new ab initio calculations of minima interaction energies at the complete basis set level of theory, are defined in the full space of relative configurations. This represents a crucial condition to provide force fields useful to carry out, in general, important molecular property simulations and to evaluate, in the present case, the spectroscopic features and the dynamical selectivity of weakly bound complexes formed by propylene oxide, a prototype chiral species, during collisions in interstellar clouds and winds, in the space and planetary atmospheres. The adopted formulation of the interaction can be readily extended to similar systems, involving heavier noble gases or diatomic molecules (H2, O2, and N2) as well as to propylene oxide dimers.
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Affiliation(s)
- Federico Palazzetti
- Dipartimento di Chimica, Biologia e Biotecnologie - Università degli Studi di Perugia, Perugia, Italy
| | - David Cappelletti
- Dipartimento di Chimica, Biologia e Biotecnologie - Università degli Studi di Perugia, Perugia, Italy
| | - Cecilia Coletti
- Dipartimento di Farmacia, Università degli Studi "G. D'Annunzio" Chieti-Pescara, Chieti, Italy
| | - Stefano Falcinelli
- Dipartimento di Ingegneria Civile ed Ambientale, Università degli Studi di Perugia, Perugia, Italy
| | - Fernando Pirani
- Dipartimento di Chimica, Biologia e Biotecnologie - Università degli Studi di Perugia, Perugia, Italy
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4
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Rotational (de-)excitation of oxophosphine (HPO) by collision with helium (He). COMPUT THEOR CHEM 2021. [DOI: 10.1016/j.comptc.2021.113355] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/24/2022]
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5
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Ben Krid A, Ajili Y, Ben Abdallah D, Dhib M, Aroui H, Hochlaf M. Explicitly correlated potential energy surface of the CH 3Cl-He van der Waals complex and applications. J Chem Phys 2021; 154:094304. [PMID: 33685174 DOI: 10.1063/5.0038677] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/17/2022] Open
Abstract
A new 3D-potential energy surface (3D-PES) for the weakly bound CH3Cl-He complex is mapped in Jacobi coordinates. Electronic structure calculations are performed using the explicitly correlated coupled clusters with single, double, and perturbative triple excitations approach in conjunction with the aug-cc-pVTZ basis set. Then, an analytical expansion of this 3D-PES is derived. This PES shows three minimal structures for collinear C-Cl-He arrangements and for He located in between two H atoms, in the plane parallel to the three H atoms, which is near the center of mass of CH3Cl. The latter form corresponds to the global minimum. Two maxima are also found, which connect the minimal structures. We then evaluated the pressure broadening coefficients of the spectral lines of CH3Cl in a helium bath based on our ab initio potential. Satisfactory agreement with experiments was observed, confirming the good accuracy of our 3D-PES. We also derived the bound rovibronic levels for ortho- and para-CH3Cl-He dimers after quantum treatment of the nuclear motions. For both clusters, computations show that although the ground vibrational state is located well above the intramolecular isomerization barriers, the rovibronic levels may be associated with a specific minimal structure. This can be explained by vibrational localization and vibrational memory effects.
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Affiliation(s)
- A Ben Krid
- Université Gustave Eiffel, COSYS/LISIS, 5 Bd Descartes, 77454 Champs sur Marne, France
| | - Y Ajili
- Laboratoire de Spectroscopie Atomique, Moléculaire et Applications LSAMA, Université de Tunis Al Manar, Tunis, Tunisia
| | - D Ben Abdallah
- Université de Tunis, Ecole Nationale Supérieure d'Ingénieurs de Tunis, Laboratoire de Spectroscopie et Dynamique Moléculaire (LSDM), 5 Av. Taha Hussein, 1008 Tunis, Tunisia
| | - M Dhib
- Université de Tunis, Ecole Nationale Supérieure d'Ingénieurs de Tunis, Laboratoire de Spectroscopie et Dynamique Moléculaire (LSDM), 5 Av. Taha Hussein, 1008 Tunis, Tunisia
| | - H Aroui
- Université de Tunis, Ecole Nationale Supérieure d'Ingénieurs de Tunis, Laboratoire de Spectroscopie et Dynamique Moléculaire (LSDM), 5 Av. Taha Hussein, 1008 Tunis, Tunisia
| | - M Hochlaf
- Université Gustave Eiffel, COSYS/LISIS, 5 Bd Descartes, 77454 Champs sur Marne, France
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6
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Bergeat A, Morales SB, Naulin C, Wiesenfeld L, Faure A. Probing Low-Energy Resonances in Water-Hydrogen Inelastic Collisions. PHYSICAL REVIEW LETTERS 2020; 125:143402. [PMID: 33064550 DOI: 10.1103/physrevlett.125.143402] [Citation(s) in RCA: 5] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Received: 06/05/2020] [Accepted: 08/17/2020] [Indexed: 06/11/2023]
Abstract
Molecular scattering at collisional energies of the order of 10-100 cm^{-1} (corresponding to kinetic temperatures in the 15-150 K range) provides insight into the details of the scattering process and, in particular, of the various resonances that appear in inelastic cross sections. In this Letter, we present a detailed experimental and theoretical study of the rotationally inelastic scattering of ground-state ortho-D_{2}O by ground-state para-H_{2} in the threshold region of the D_{2}O(0_{00}→2_{02}) transition at 35.9 cm^{-1}. The measurements were performed with a molecular crossed beam apparatus with variable collision angle, thence with variable collisional energy. Calculations were carried out with the coupled-channel method combined with a dedicated high-level D_{2}O-H_{2} intermolecular potential. Our theoretical cross section 0_{00}→2_{02} is found to display several resonance peaks in perfect agreement with the experimental work, in their absolute positions and relative intensities. We show that those peaks are mostly due to shape resonances, characterized here for the first time for a polyatomic molecule colliding with a diatom.
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Affiliation(s)
- A Bergeat
- Université de Bordeaux, CNRS, Bordeaux INP, ISM, UMR5255, F-33405 Talence, France
| | - S B Morales
- Université de Bordeaux, CNRS, Bordeaux INP, ISM, UMR5255, F-33405 Talence, France
| | - C Naulin
- Université de Bordeaux, CNRS, Bordeaux INP, ISM, UMR5255, F-33405 Talence, France
| | - L Wiesenfeld
- Université Paris-Saclay, CNRS, Laboratoire Aimé Cotton, F-91405 Orsay, France
| | - A Faure
- Université Grenoble Alpes, CNRS, IPAG, F-38000 Grenoble, France
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7
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Koner D, Meuwly M. Permutationally Invariant, Reproducing Kernel-Based Potential Energy Surfaces for Polyatomic Molecules: From Formaldehyde to Acetone. J Chem Theory Comput 2020; 16:5474-5484. [DOI: 10.1021/acs.jctc.0c00535] [Citation(s) in RCA: 25] [Impact Index Per Article: 6.3] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/27/2023]
Affiliation(s)
- Debasish Koner
- Department of Chemistry, University of Basel, Klingelbergstrasse 80, 4056 Basel, Switzerland
| | - Markus Meuwly
- Department of Chemistry, University of Basel, Klingelbergstrasse 80, 4056 Basel, Switzerland
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8
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Császár AG, Simkó I, Szidarovszky T, Groenenboom GC, Karman T, van der Avoird A. Rotational-vibrational resonance states. Phys Chem Chem Phys 2020; 22:15081-15104. [PMID: 32458891 DOI: 10.1039/d0cp00960a] [Citation(s) in RCA: 7] [Impact Index Per Article: 1.8] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/21/2022]
Abstract
Resonance states are characterized by an energy that is above the lowest dissociation threshold of the potential energy hypersurface of the system and thus resonances have finite lifetimes. All molecules possess a large number of long- and short-lived resonance (quasibound) states. A considerable number of rotational-vibrational resonance states are accessible not only via quantum-chemical computations but also by spectroscopic and scattering experiments. In a number of chemical applications, most prominently in spectroscopy and reaction dynamics, consideration of rotational-vibrational resonance states is becoming more and more common. There are different first-principles techniques to compute and rationalize rotational-vibrational resonance states: one can perform scattering calculations or one can arrive at rovibrational resonances using variational or variational-like techniques based on methods developed for determining bound eigenstates. The latter approaches can be based either on the Hermitian (L2, square integrable) or non-Hermitian (non-L2) formalisms of quantum mechanics. This Perspective reviews the basic concepts related to and the relevance of shape and Feshbach-type rotational-vibrational resonance states, discusses theoretical methods and computational tools allowing their efficient determination, and shows numerical examples from the authors' previous studies on the identification and characterization of rotational-vibrational resonances of polyatomic molecular systems.
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Affiliation(s)
- Attila G Császár
- MTA-ELTE Complex Chemical Systems Research Group, P. O. Box 32, H-1518 Budapest 112, Hungary.
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9
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Surin LA, Tarabukin IV, Hermanns M, Heyne B, Schlemmer S, Kalugina YN, van der Avoird A. Ab initio potential energy surface and microwave spectrum of the NH 3-N 2 van der Waals complex. J Chem Phys 2020; 152:234304. [PMID: 32571071 DOI: 10.1063/5.0011557] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/14/2022] Open
Abstract
We present a five-dimensional intermolecular potential energy surface (PES) of the NH3-N2 complex, bound state calculations, and new microwave (MW) measurements that provide information on the structure of this complex and a critical test of the potential. Ab initio calculations were carried out using the explicitly correlated coupled cluster [CCSD(T)-F12a] approach with the augmented correlation-consistent aug-cc-pVTZ basis set. The global minimum of the PES corresponds to a configuration in which the angle between the NH3 symmetry axis and the intermolecular axis is 58.7° with the N atom of the NH3 unit closest to the N2 unit, which is nearly parallel to the NH3 symmetry axis. The intermolecular distance is 7.01 a0, and the binding energy De is 250.6 cm-1. The bound rovibrational levels of the four nuclear spin isomers of the complex, which are formed when ortho/para (o/p)-NH3 combines with (o/p)-N2, were calculated on this intermolecular potential surface. The computed dissociation energies D0 are 144.91 cm-1, 146.50 cm-1, 152.29 cm-1, and 154.64 cm-1 for (o)-NH3-(o)-N2, (o)-NH3-(p)-N2, (p)-NH3-(o)-N2, and (p)-NH3-(p)-N2, respectively. Guided by these calculations, the pure rotational transitions of the NH3-N2 van der Waals complex were observed in the frequency range of 13-27 GHz using the chirped-pulse Fourier-transform MW technique. A complicated hyperfine structure due to three quadrupole 14N nuclei was partly resolved and examined for all four nuclear spin isomers of the complex. Newly obtained data definitively established the K values (the projection of the angular momentum J on the intermolecular axis) for the lowest states of the different NH3-N2 nuclear spin isomers.
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Affiliation(s)
- Leonid A Surin
- Institute of Spectroscopy, Russian Academy of Sciences, Fizicheskaya Str. 5, 108840 Troitsk, Moscow, Russia
| | - Ivan V Tarabukin
- Institute of Spectroscopy, Russian Academy of Sciences, Fizicheskaya Str. 5, 108840 Troitsk, Moscow, Russia
| | - Marius Hermanns
- I. Physikalisches Institut, University of Cologne, Zülpicher Str. 77, 50937 Cologne, Germany
| | - Bettina Heyne
- I. Physikalisches Institut, University of Cologne, Zülpicher Str. 77, 50937 Cologne, Germany
| | - Stephan Schlemmer
- I. Physikalisches Institut, University of Cologne, Zülpicher Str. 77, 50937 Cologne, Germany
| | - Yulia N Kalugina
- Institute of Spectroscopy, Russian Academy of Sciences, Fizicheskaya Str. 5, 108840 Troitsk, Moscow, Russia
| | - Ad van der Avoird
- Theoretical Chemistry, Institute for Molecules and Materials, Radboud University, Heyendaalseweg 135, 6525 AJ Nijmegen, The Netherlands
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10
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Ben Khalifa M, Quintas-Sánchez E, Dawes R, Hammami K, Wiesenfeld L. Rotational quenching of an interstellar gas thermometer: CH 3CNHe collisions. Phys Chem Chem Phys 2020; 22:17494-17502. [PMID: 32716451 DOI: 10.1039/d0cp02985h] [Citation(s) in RCA: 6] [Impact Index Per Article: 1.5] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/21/2022]
Abstract
Among all the molecular species found in the interstellar medium, molecules with threefold symmetry axes play a special role, as their rotational spectroscopy allows them to act as practical gas thermometers. Methyl-cyanide (CH3CN) is the second most abundant of those (after ammonia). We compute in this paper the collisional dynamics of methyl-cyanide in collision with helium, for both the A- and the E-symmetries of CH3CN. The potential energy surface is determined using the CCSD(T)-F12b formalism and fit with convenient analytic functions. We compute the rotationally inelastic cross sections for all levels up to 510 cm-1 of collision energy, employing at low energy exact Coupled Channels methods, and at higher energies, approximate Coupled States methods. For temperatures from 7 K up to 300 K, rates of quenching are computed and most are found to differ from those reported earlier (up to a factor of a thousand), calling for a possible reexamination of the temperatures assigned to low density gasses.
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Affiliation(s)
- M Ben Khalifa
- Laboratoire Aimé-Cotton, CNRS and Université Paris-Saclay, Orsay, France. and Laboratoire de Spectroscopie Atomique Moléculaire et Applications, Université Tunis El-Manar, Tunis, Tunisie.
| | - E Quintas-Sánchez
- Missouri University of Science and Technology, Rolla, MO 65409-0010, USA
| | - R Dawes
- Missouri University of Science and Technology, Rolla, MO 65409-0010, USA
| | - K Hammami
- Laboratoire de Spectroscopie Atomique Moléculaire et Applications, Université Tunis El-Manar, Tunis, Tunisie.
| | - L Wiesenfeld
- Laboratoire Aimé-Cotton, CNRS and Université Paris-Saclay, Orsay, France.
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11
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Patkowski K. Recent developments in symmetry‐adapted perturbation theory. WILEY INTERDISCIPLINARY REVIEWS-COMPUTATIONAL MOLECULAR SCIENCE 2019. [DOI: 10.1002/wcms.1452] [Citation(s) in RCA: 53] [Impact Index Per Article: 10.6] [Reference Citation Analysis] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 01/16/2023]
Affiliation(s)
- Konrad Patkowski
- Department of Chemistry and Biochemistry Auburn University Auburn Alabama
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12
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Gao Z, Loreau J, van der Avoird A, van de Meerakker SYT. Direct observation of product-pair correlations in rotationally inelastic collisions of ND 3 with D 2. Phys Chem Chem Phys 2019; 21:14033-14041. [PMID: 30649107 DOI: 10.1039/c8cp07109h] [Citation(s) in RCA: 8] [Impact Index Per Article: 1.6] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/21/2022]
Abstract
We present a combined experimental and theoretical study of state-to-state inelastic scattering of ND3(j = 11-) with D2 (j = 0, 1, 2, 3) molecules at collision energies around 800 cm-1. Using a crossed molecular beam apparatus which employs the combination of Stark deceleration and velocity map imaging, we observe the correlated rotational excitations of both collision partners. For D2, both elastic (ΔjD2 = 0), inelastic excitation (j = 0 →j = 2) and inelastic de-excitation (j = 2 →j = 0) processes are observed. For a number of final ND3 states, inelastic channels in which D2 is rotationally excited or de-excited appear surprisingly strong. The experimental results are in excellent agreement with the predictions from quantum scattering calculations which are based on an ab initio ND3-D2 potential energy surface.
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Affiliation(s)
- Zhi Gao
- Institute for Molecules and Materials, Radboud University, Heyendaalseweg 135, 6525 AJ Nijmegen, The Netherlands.
| | - Jérôme Loreau
- Service de Chimie Quantique et Photophysique, Université libre de Bruxelles, CP 160/09, 1050 Brussels, Belgium.
| | - Ad van der Avoird
- Institute for Molecules and Materials, Radboud University, Heyendaalseweg 135, 6525 AJ Nijmegen, The Netherlands.
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13
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Dawes R, Quintas‐Sánchez E. THE CONSTRUCTION OF AB INITIO‐BASED POTENTIAL ENERGY SURFACES. REVIEWS IN COMPUTATIONAL CHEMISTRY 2018. [DOI: 10.1002/9781119518068.ch5] [Citation(s) in RCA: 13] [Impact Index Per Article: 2.2] [Reference Citation Analysis] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 11/07/2022]
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14
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Puri P, Mills M, West EP, Schneider C, Hudson ER. High-resolution collision energy control through ion position modulation in atom-ion hybrid systems. THE REVIEW OF SCIENTIFIC INSTRUMENTS 2018; 89:083112. [PMID: 30184618 DOI: 10.1063/1.5031145] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.2] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Received: 03/28/2018] [Accepted: 07/30/2018] [Indexed: 06/08/2023]
Abstract
We demonstrate an ion shuttling technique for high-resolution control of atom-ion collision energy by translating an ion held within a radio-frequency trap through a magneto-optical atom trap. The technique is demonstrated both experimentally and through numerical simulations, with the experimental results indicating control of ion kinetic energies from 0.05 to 1 K with a fractional resolution of ∼10 and the simulations demonstrating that kinetic energy control up to 120 K with a maximum predicted resolution of ∼100 is possible, offering order-of-magnitude improvements over most alternative techniques. Finally, we perform a proof-of-principle chemistry experiment using this technique and outline how the method may be refined in the future and applied to the study of molecular ion chemistry.
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Affiliation(s)
- Prateek Puri
- Department of Physics and Astronomy, University of California, Los Angeles, Los Angeles, California 90095, USA
| | - Michael Mills
- Department of Physics and Astronomy, University of California, Los Angeles, Los Angeles, California 90095, USA
| | - Elizabeth P West
- Department of Physics and Astronomy, University of California, Los Angeles, Los Angeles, California 90095, USA
| | - Christian Schneider
- Department of Physics and Astronomy, University of California, Los Angeles, Los Angeles, California 90095, USA
| | - Eric R Hudson
- Department of Physics and Astronomy, University of California, Los Angeles, Los Angeles, California 90095, USA
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15
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Asselin P, Belkhodja Y, Jabri A, Potapov A, Loreau J, van der Avoird A. Rovibrational laser jet-cooled spectroscopy of the NH 3–Ar complex in the ν2 umbrella region of NH 3: comparison between new infrared data and an ab initio calculated spectrum. Mol Phys 2018. [DOI: 10.1080/00268976.2018.1471533] [Citation(s) in RCA: 4] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/16/2022]
Affiliation(s)
- Pierre Asselin
- Sorbonne Université, CNRS, MONARIS, UMR 8233, Paris, France
| | | | - Atef Jabri
- Sorbonne Université, CNRS, MONARIS, UMR 8233, Paris, France
| | - Alexey Potapov
- Laboratory Astrophysics Group of the Max Planck Institute for Astronomy, Friedrich Schiller University Jena, Jena, Germany
| | - Jérôme Loreau
- Service de Chimie Quantique et Photophysique, Université libre de Bruxelles (ULB), Brussels, Belgium
| | - Ad van der Avoird
- Theoretical Chemistry, Institute for Molecules and Materials, Radboud University, Nijmegen, The Netherlands
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16
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17
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Doppelbauer MJ, Schullian O, Loreau J, Vaeck N, van der Avoird A, Rennick CJ, Softley TP, Heazlewood BR. Using a direct simulation Monte Carlo approach to model collisions in a buffer gas cell. J Chem Phys 2017; 146:044302. [PMID: 28147514 DOI: 10.1063/1.4974253] [Citation(s) in RCA: 8] [Impact Index Per Article: 1.1] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/14/2022] Open
Abstract
A direct simulation Monte Carlo (DSMC) method is applied to model collisions between He buffer gas atoms and ammonia molecules within a buffer gas cell. State-to-state cross sections, calculated as a function of the collision energy, enable the inelastic collisions between He and NH3 to be considered explicitly. The inclusion of rotational-state-changing collisions affects the translational temperature of the beam, indicating that elastic and inelastic processes should not be considered in isolation. The properties of the cold molecular beam exiting the cell are examined as a function of the cell parameters and operating conditions; the rotational and translational energy distributions are in accord with experimental measurements. The DSMC calculations show that thermalisation occurs well within the typical 10-20 mm length of many buffer gas cells, suggesting that shorter cells could be employed in many instances-yielding a higher flux of cold molecules.
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Affiliation(s)
- Maximilian J Doppelbauer
- Department of Chemistry, University of Oxford, Chemistry Research Laboratory, 12 Mansfield Road, Oxford OX1 3TA, United Kingdom
| | - Otto Schullian
- Department of Chemistry, University of Oxford, Chemistry Research Laboratory, 12 Mansfield Road, Oxford OX1 3TA, United Kingdom
| | - Jerome Loreau
- Service de Chimie Quantique et Photophysique, Université Libre de Bruxelles (ULB), CP 160/09, 50 Ave. F.D. Roosevelt, 1050 Brussels, Belgium
| | - Nathalie Vaeck
- Service de Chimie Quantique et Photophysique, Université Libre de Bruxelles (ULB), CP 160/09, 50 Ave. F.D. Roosevelt, 1050 Brussels, Belgium
| | - Ad van der Avoird
- Institute for Molecules and Materials, Radboud University, Heyendaalseweg 135, 6525 AJ Nijmegen, The Netherlands
| | - Christopher J Rennick
- Department of Chemistry, University of Oxford, Chemistry Research Laboratory, 12 Mansfield Road, Oxford OX1 3TA, United Kingdom
| | - Timothy P Softley
- University of Birmingham, Edgbaston, Birmingham B15 2TT, United Kingdom
| | - Brianna R Heazlewood
- Department of Chemistry, University of Oxford, Chemistry Research Laboratory, 12 Mansfield Road, Oxford OX1 3TA, United Kingdom
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18
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Surin L, Schnell M. Rotational spectrum of the NH 3–He van der Waals complex. EPJ WEB OF CONFERENCES 2017. [DOI: 10.1051/epjconf/201713203045] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/14/2022] Open
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19
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Onvlee J, Vogels SN, van de Meerakker SYT. Unraveling Cold Molecular Collisions: Stark Decelerators in Crossed-Beam Experiments. Chemphyschem 2016; 17:3583-3595. [PMID: 27471830 DOI: 10.1002/cphc.201600604] [Citation(s) in RCA: 8] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/06/2016] [Indexed: 11/11/2022]
Abstract
In the last two decades, enormous progress has been made in the manipulation of molecular beams. In particular, molecular decelerators have been developed with which advanced control over neutral molecules in a beam can be achieved. By using arrays of inhomogeneous and time-varying electric (or magnetic) fields, bunches of molecules can be produced with a tunable velocity, narrow velocity spreads, and almost perfect quantum-state purity. These monochromatic or "tamed" molecular beams are ideally suited to be used in crossed-molecular-beam scattering experiments. Here, we review the first generation of these "cold and controlled" scattering experiments that have been conducted in the last decade and discuss the prospects for this emerging field of research in the years to come.
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Affiliation(s)
- Jolijn Onvlee
- Radboud University, Institute for Molecules and Materials, Heijendaalseweg 135, 6525 AJ, Nijmegen, the Netherlands
| | - Sjoerd N Vogels
- Radboud University, Institute for Molecules and Materials, Heijendaalseweg 135, 6525 AJ, Nijmegen, the Netherlands
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20
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Jachymski K, Hapka M, Jankunas J, Osterwalder A. Experimental and Theoretical Studies of Low‐Energy Penning Ionization of NH
3
, CH
3
F, and CHF
3. Chemphyschem 2016; 17:3776-3782. [DOI: 10.1002/cphc.201600608] [Citation(s) in RCA: 5] [Impact Index Per Article: 0.6] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/08/2016] [Revised: 08/02/2016] [Indexed: 11/10/2022]
Affiliation(s)
- Krzysztof Jachymski
- Faculty of Physics University of Warsaw Pasteura 5 02-093 Warsaw Poland
- Institute for Theoretical Physics III and Center for Integrated Quantum Science and Technology University of Stuttgart Pfaffenwaldring 57 70550 Stuttgart Germany
| | - Michał Hapka
- Faculty of Chemistry University of Warsaw Pasteura 1 02-093 Warsaw Poland
| | - Justin Jankunas
- Institute for Chemical Sciences and Engineering Ecole Polytechnique Fédérale de Lausanne (EPFL) 1015 Lausanne Switzerland
- Deceased
| | - Andreas Osterwalder
- Institute for Chemical Sciences and Engineering Ecole Polytechnique Fédérale de Lausanne (EPFL) 1015 Lausanne Switzerland
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21
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Walker KM, Dumouchel F, Lique F, Dawes R. The first potential energy surfaces for the C6H−–H2 and C6H−–He collisional systems and their corresponding inelastic cross sections. J Chem Phys 2016; 145:024314. [DOI: 10.1063/1.4955200] [Citation(s) in RCA: 21] [Impact Index Per Article: 2.6] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/14/2022] Open
Affiliation(s)
- Kyle M. Walker
- LOMC-UMR 6294, CNRS-Université du Havre, 25 rue Philippe Lebon, BP 1123, 76 063 Le Havre Cedex, France
| | - Fabien Dumouchel
- LOMC-UMR 6294, CNRS-Université du Havre, 25 rue Philippe Lebon, BP 1123, 76 063 Le Havre Cedex, France
| | - François Lique
- LOMC-UMR 6294, CNRS-Université du Havre, 25 rue Philippe Lebon, BP 1123, 76 063 Le Havre Cedex, France
| | - Richard Dawes
- Department of Chemistry, Missouri University of Science and Technology, Rolla, Missouri 65409, USA
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22
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Dawes R, Ndengué SA. Single- and multireference electronic structure calculations for constructing potential energy surfaces. INT REV PHYS CHEM 2016. [DOI: 10.1080/0144235x.2016.1195102] [Citation(s) in RCA: 35] [Impact Index Per Article: 4.4] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/21/2022]
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23
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Jankunas J, Jachymski K, Hapka M, Osterwalder A. Communication: Importance of rotationally inelastic processes in low-energy Penning ionization of CHF3. J Chem Phys 2016; 144:221102. [DOI: 10.1063/1.4953908] [Citation(s) in RCA: 10] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/14/2022] Open
Affiliation(s)
- Justin Jankunas
- Institute for Chemical Sciences and Engineering, Ecole Polytechnique Fédérale de Lausanne (EPFL), 1015 Lausanne, Switzerland
| | - Krzysztof Jachymski
- Faculty of Physics, University of Warsaw, Pasteura 5, 02-093 Warsaw, Poland
- Institute for Theoretical Physics III and Center for Integrated Quantum Science and Technology, University of Stuttgart, Pfaffenwaldring 57, 70550 Stuttgart, Germany
| | - Michał Hapka
- Faculty of Chemistry, University of Warsaw, Pasteura 1, 02-093 Warsaw, Poland
| | - Andreas Osterwalder
- Institute for Chemical Sciences and Engineering, Ecole Polytechnique Fédérale de Lausanne (EPFL), 1015 Lausanne, Switzerland
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24
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Costes M, Naulin C. Observation of quantum dynamical resonances in near cold inelastic collisions of astrophysical molecules. Chem Sci 2016; 7:2462-2469. [PMID: 28660016 PMCID: PMC5477044 DOI: 10.1039/c5sc04557f] [Citation(s) in RCA: 31] [Impact Index Per Article: 3.9] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/26/2015] [Accepted: 01/07/2016] [Indexed: 12/28/2022] Open
Abstract
Quantum resonances in inelastic collisions, predicted by theory and detected at low energies in a crossed-beam experiment, are reviewed.
This mini review summarizes experimental findings of quantum dynamical resonances in inelastic collisions at energies equivalent to temperatures of a few to a few tens of Kelvin, corresponding to physical conditions prevailing in dense molecular clouds of the interstellar medium. Information obtained is thus relevant to collision energy transfer modelling in such media. Crossed-beam scattering experiments performed at Bordeaux university for inelastic collisions of important astrophysical molecules such as CO with H2 or He and O2 with H2 are described. The peaks that show up in the collision energy dependence of the state-to-state integral cross sections for the lowest rotational excitation transitions reveal the quantum nature of such processes. They are ascribed as shape and Feshbach resonances by comparison with the results of close coupling quantum mechanical calculations performed concomitantly on accurate potential energy surfaces.
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Affiliation(s)
- Michel Costes
- Université de Bordeaux , Institut des Sciences Moléculaires , 33405 Talence Cedex , France . .,CNRS , UMR 5255 , 33405 Talence Cedex , France
| | - Christian Naulin
- Université de Bordeaux , Institut des Sciences Moléculaires , 33405 Talence Cedex , France . .,CNRS , UMR 5255 , 33405 Talence Cedex , France
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25
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Loreau J, van der Avoird A. Scattering of NH3 and ND3 with rare gas atoms at low collision energy. J Chem Phys 2015; 143:184303. [DOI: 10.1063/1.4935259] [Citation(s) in RCA: 17] [Impact Index Per Article: 1.9] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/14/2022] Open
Affiliation(s)
- J. Loreau
- Service de Chimie Quantique et Photophysique, Université Libre de Bruxelles (ULB) CP 160/09, 50 av. F.D. Roosevelt, 1050 Brussels, Belgium
| | - A. van der Avoird
- Theoretical Chemistry, Institute for Molecules and Materials, Radboud University, Heyendaalseweg 135, 6525 AJ Nijmegen, The Netherlands
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26
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Schullian O, Loreau J, Vaeck N, Avoird AVD, Heazlewood B, Rennick C, Softley T. Simulating rotationally inelastic collisions using a direct simulation Monte Carlo method. Mol Phys 2015. [DOI: 10.1080/00268976.2015.1098740] [Citation(s) in RCA: 7] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/22/2022]
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27
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van der Avoird A, Loreau J, Alexander MH, van de Meerakker SYT, Dagdigian PJ. Resonances in rotationally inelastic scattering of NH3 and ND3 with H2. J Chem Phys 2015; 143:044312. [PMID: 26233134 DOI: 10.1063/1.4927074] [Citation(s) in RCA: 21] [Impact Index Per Article: 2.3] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/14/2022] Open
Affiliation(s)
- Ad van der Avoird
- Institute for Molecules and Materials, Radboud University, Heyendaalseweg 135, 6525 AJ Nijmegen, The Netherlands
| | - Jérôme Loreau
- Service de Chimie Quantique et Photophysique C. P. 160/09, Université Libre de Bruxelles (ULB), 50 Ave. F. D. Roosevelt, 1050 Brussels, Belgium
| | - Millard H. Alexander
- Department of Chemistry and Biochemistry and Institute for Physical Science and Technology, University of Maryland, College Park, Maryland 20742-2021, USA
| | | | - Paul J. Dagdigian
- Department of Chemistry, The Johns Hopkins University, Baltimore, Maryland 21218-2685, USA
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28
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Tkáč O, Saha AK, Loreau J, Ma Q, Dagdigian PJ, Parker DH, van der Avoird A, Orr-Ewing AJ. Rotationally inelastic scattering of ND3with H2as a probe of the intermolecular potential energy surface. Mol Phys 2015. [DOI: 10.1080/00268976.2015.1059958] [Citation(s) in RCA: 13] [Impact Index Per Article: 1.4] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/23/2022]
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29
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Tkáč O, Saha AK, Loreau J, Parker DH, van der Avoird A, Orr-Ewing AJ. Rotationally Inelastic Scattering of Quantum-State-Selected ND3 with Ar. J Phys Chem A 2015; 119:5979-87. [PMID: 25532415 DOI: 10.1021/jp5115042] [Citation(s) in RCA: 8] [Impact Index Per Article: 0.9] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/20/2022]
Abstract
Rotationally inelastic scattering of ND3 with Ar is studied at mean collision energies of 410 and 310 cm(–1). In the experimental component of the study, ND3 molecules are prepared by supersonic expansion and subsequent hexapole state selection in the ground electronic and vibrational levels and in the jk(±) = 1(1) rotational level. A beam of state-selected ND3 molecules is crossed with a beam of Ar, and scattered ND3 molecules are detected in single final j′k′(±) quantum states using resonance enhanced multiphoton ionization spectroscopy. State-to-state differential cross sections for rotational-level changing collisions are obtained by velocity map imaging. The experimental measurements are compared with close-coupling quantum-mechanical scattering calculations performed using an ab initio potential energy surface. The computed DCSs agree well with the experimental measurements, confirming the high quality of the potential energy surface. The angular distributions are dominated by forward scattering for all measured final rotational and vibrational inversion symmetry states. This outcome is in contrast to our recent results for inelastic scattering of ND3 with He, where we observed significant amount of sideways and backward scattering for some final rotational levels of ND3. The differences between He and Ar collision partners are explained by differences in the potential energy surfaces that govern the scattering dynamics.
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Affiliation(s)
- Ondřej Tkáč
- †Laboratorium für Physikalische Chemie, ETH Zürich, CH-8093 Zürich, Switzerland
| | - Ashim K Saha
- ‡Institute for Molecules and Materials, Radboud University Nijmegen, Toernooiveld 1, 6525ED Nijmegen, The Netherlands
| | - Jérôme Loreau
- §Service de Chimie Quantique et Photophysique, Université Libre de Bruxelles (ULB) CP 160/09, 50 Av. F. D. Roosevelt, 1050 Brussels, Belgium
| | - David H Parker
- ‡Institute for Molecules and Materials, Radboud University Nijmegen, Toernooiveld 1, 6525ED Nijmegen, The Netherlands
| | - Ad van der Avoird
- ‡Institute for Molecules and Materials, Radboud University Nijmegen, Toernooiveld 1, 6525ED Nijmegen, The Netherlands
| | - Andrew J Orr-Ewing
- ∥School of Chemistry, University of Bristol, Cantock's Close, Bristol BS8 1TS, U.K
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30
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Loreau J, Liévin J, Scribano Y, van der Avoird A. Potential energy surface and bound states of the NH3-Ar and ND3-Ar complexes. J Chem Phys 2015; 141:224303. [PMID: 25494745 DOI: 10.1063/1.4903047] [Citation(s) in RCA: 19] [Impact Index Per Article: 2.1] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/11/2022] Open
Abstract
A new, four-dimensional potential energy surface for the interaction of NH3 and ND3 with Ar is computed using the coupled-cluster method with single, double, and perturbative triple excitations and large basis sets. The umbrella motion of the ammonia molecule is explicitly taken into account. The bound states of both NH3-Ar and ND3-Ar are calculated on this potential for total angular momentum values from J = 0 to 10, with the inclusion of Coriolis interactions. The energies and splittings of the rovibrational levels are in excellent agreement with the extensive high-resolution spectroscopic data accumulated over the years in the infrared and microwave regions for both complexes, which demonstrates the quality of the potential energy surface.
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Affiliation(s)
- J Loreau
- Service de Chimie Quantique et Photophysique, Université Libre de Bruxelles (ULB) CP 160/09, 50 av. F.D. Roosevelt, 1050 Brussels, Belgium
| | - J Liévin
- Service de Chimie Quantique et Photophysique, Université Libre de Bruxelles (ULB) CP 160/09, 50 av. F.D. Roosevelt, 1050 Brussels, Belgium
| | - Y Scribano
- Laboratoire Univers et Particules de Montpellier, Université de Montpellier II, LUPM - UMR CNRS 5299, 34095 Montpellier Cedex, France
| | - A van der Avoird
- Theoretical Chemistry, Institute for Molecules and Materials, Radboud University Nijmegen, Heyendaalseweg 135, 6525 AJ Nijmegen, The Netherlands
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31
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Bergeat A, Onvlee J, Naulin C, van der Avoird A, Costes M. Quantum dynamical resonances in low-energy CO(j = 0) + He inelastic collisions. Nat Chem 2015; 7:349-53. [PMID: 25803474 DOI: 10.1038/nchem.2204] [Citation(s) in RCA: 62] [Impact Index Per Article: 6.9] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/22/2014] [Accepted: 02/12/2015] [Indexed: 11/09/2022]
Abstract
In molecular collisions, long-lived complexes may be formed that correspond to quasi-bound states in the van der Waals potential and give rise to peaks in the collision energy-dependent cross-sections. They are known as 'resonances' and their experimental detection remains difficult because their signatures are extremely challenging to resolve. Here, we show a complete characterization of quantum-dynamical resonances occurring in CO-He inelastic collisions with rotational CO(j = 0->1) excitation. Crossed-beam scattering experiments were performed at collision energies as low as 4 cm(-1), equivalent to a temperature of 4 K. Resonance structures in the measured cross-sections were identified by comparison with quantum-mechanical calculations. The excellent agreement found confirms that the potential energy surfaces describing the CO-He van der Waals interaction are perfectly suitable for calculating state-to-state (de)excitation rate coefficients at the very low temperatures needed in chemical modelling of the interstellar medium. We also computed these rate coefficients.
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Affiliation(s)
- Astrid Bergeat
- 1] Université de Bordeaux, Institut des Sciences Moléculaires, Talence Cedex 33405, France [2] CNRS, UMR 5255, Talence Cedex 33405, France
| | - Jolijn Onvlee
- Radboud University Nijmegen, Institute for Molecules and Materials, Heijendaalseweg 135, Nijmegen 6525 AJ, The Netherlands
| | - Christian Naulin
- 1] Université de Bordeaux, Institut des Sciences Moléculaires, Talence Cedex 33405, France [2] CNRS, UMR 5255, Talence Cedex 33405, France
| | - Ad van der Avoird
- Radboud University Nijmegen, Institute for Molecules and Materials, Heijendaalseweg 135, Nijmegen 6525 AJ, The Netherlands
| | - Michel Costes
- 1] Université de Bordeaux, Institut des Sciences Moléculaires, Talence Cedex 33405, France [2] CNRS, UMR 5255, Talence Cedex 33405, France
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32
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Surin LA, Potapov A, Dolgov AA, Tarabukin IV, Panfilov VA, Schlemmer S, Kalugina YN, Faure A, van der Avoird A. Rotational study of the NH3–CO complex: Millimeter-wave measurements and ab initio calculations. J Chem Phys 2015; 142:114308. [DOI: 10.1063/1.4915119] [Citation(s) in RCA: 14] [Impact Index Per Article: 1.6] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/14/2022] Open
Affiliation(s)
- L. A. Surin
- I. Physikalisches Institut, University of Cologne, Zülpicher Str. 77, 50937 Cologne, Germany
- Institute of Spectroscopy, Russian Academy of Sciences, Fizicheskaya Str. 5, 142190 Troitsk, Moscow, Russia
| | - A. Potapov
- I. Physikalisches Institut, University of Cologne, Zülpicher Str. 77, 50937 Cologne, Germany
| | - A. A. Dolgov
- Institute of Spectroscopy, Russian Academy of Sciences, Fizicheskaya Str. 5, 142190 Troitsk, Moscow, Russia
| | - I. V. Tarabukin
- Institute of Spectroscopy, Russian Academy of Sciences, Fizicheskaya Str. 5, 142190 Troitsk, Moscow, Russia
| | - V. A. Panfilov
- Institute of Spectroscopy, Russian Academy of Sciences, Fizicheskaya Str. 5, 142190 Troitsk, Moscow, Russia
| | - S. Schlemmer
- I. Physikalisches Institut, University of Cologne, Zülpicher Str. 77, 50937 Cologne, Germany
| | - Y. N. Kalugina
- Department of Optics and Spectroscopy, Tomsk State University, 36 Lenin av., 634050 Tomsk, Russia
| | - A. Faure
- Université de Grenoble Alpes, IPAG, F-38000 Grenoble, France
- CNRS, IPAG, F-38000 Grenoble, France
| | - A. van der Avoird
- Theoretical Chemistry, Institute for Molecules and Materials, Radboud University Nijmegen, Heyendaalseweg 135, 6525 AJ Nijmegen, The Netherlands
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33
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Massó H, Wiesenfeld L. The HCO+–H2 van der Waals interaction: Potential energy and scattering. J Chem Phys 2014; 141:184301. [DOI: 10.1063/1.4900856] [Citation(s) in RCA: 19] [Impact Index Per Article: 1.9] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/14/2022] Open
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34
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Naulin C, Costes M. Experimental search for scattering resonances in near cold molecular collisions. INT REV PHYS CHEM 2014. [DOI: 10.1080/0144235x.2014.957565] [Citation(s) in RCA: 31] [Impact Index Per Article: 3.1] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/24/2022]
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35
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Kalugina YN, Buryak IA, Ajili Y, Vigasin AA, Jaidane NE, Hochlaf M. Explicit correlation treatment of the potential energy surface of CO2 dimer. J Chem Phys 2014; 140:234310. [DOI: 10.1063/1.4882900] [Citation(s) in RCA: 50] [Impact Index Per Article: 5.0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/14/2022] Open
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36
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Tkáč O, Orr-Ewing AJ, Dagdigian PJ, Alexander MH, Onvlee J, van der Avoird A. Collision dynamics of symmetric top molecules: a comparison of the rotationally inelastic scattering of CD3 and ND3 with He. J Chem Phys 2014; 140:134308. [PMID: 24712794 DOI: 10.1063/1.4869596] [Citation(s) in RCA: 10] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/14/2022] Open
Abstract
We compare rotationally inelastic scattering of deuterated methyl radicals (CD3) and ammonia (ND3) in collisions with helium using close-coupling quantum-mechanical scattering calculations performed with ab initio potential energy surfaces (PESs). The theoretical methods have been rigorously tested against angle-resolved experimental measurements obtained using crossed molecular beam apparatuses in combination with velocity map imaging [O. Tkáč, A. G. Sage, S. J. Greaves, A. J. Orr-Ewing, P. J. Dagdigian, Q. Ma, and M. H. Alexander, Chem. Sci. 4, 4199 (2013); O. Tkáč, A. K. Saha, J. Onvlee, C.-H. Yang, G. Sarma, C. K. Bishwakarma, S. Y. T. van de Meerakker, A. van der Avoird, D. H. Parker, and A. J. Orr-Ewing, Phys. Chem. Chem. Phys. 16, 477 (2014)]. Common features of the scattering dynamics of these two symmetric top molecules, one closed-shell and the other an open-shell radical, are identified and discussed. Two types of anisotropies in the PES influence the interaction of an atom with a nonlinear polyatomic molecule. The effects of these anisotropies can be clearly seen in the state-to-state integral cross sections out of the lowest CD3 rotational levels of each nuclear spin symmetry at a collision energy of 440 cm(-1). Similarities and differences in the differential cross sections for the ND3-He and CD3-He systems can be linked to the coupling terms derived from the PESs which govern particular initial to final rotational level transitions.
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Affiliation(s)
- Ondřej Tkáč
- School of Chemistry, University of Bristol, Cantock's Close, Bristol BS8 1TS, United Kingdom
| | - Andrew J Orr-Ewing
- School of Chemistry, University of Bristol, Cantock's Close, Bristol BS8 1TS, United Kingdom
| | - Paul J Dagdigian
- Department of Chemistry, The Johns Hopkins University, Baltimore, Maryland 21218-2685, USA
| | - Millard H Alexander
- Department of Chemistry and Biochemistry and Institute for Physical Science and Technology, University of Maryland, College Park, Maryland 20742-2021, USA
| | - Jolijn Onvlee
- Institute for Molecules and Materials, Radboud University Nijmegen, Heyendaalseweg 135, 6525AJ Nijmegen, The Netherlands
| | - Ad van der Avoird
- Institute for Molecules and Materials, Radboud University Nijmegen, Heyendaalseweg 135, 6525AJ Nijmegen, The Netherlands
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37
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Smith DGA, Patkowski K, Trinh D, Balakrishnan N, Lee TG, Forrey RC, Yang BH, Stancil PC. Highly Correlated Electronic Structure Calculations of the He–C3 van der Waals Complex and Collision-Induced Rotational Transitions of C3. J Phys Chem A 2014; 118:6351-60. [DOI: 10.1021/jp412048w] [Citation(s) in RCA: 12] [Impact Index Per Article: 1.2] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/30/2022]
Affiliation(s)
- Daniel G. A. Smith
- Department
of Chemistry and Biochemistry, Auburn University, 179 Chemistry Building, Auburn, Alabama 36849, United States
| | - Konrad Patkowski
- Department
of Chemistry and Biochemistry, Auburn University, 179 Chemistry Building, Auburn, Alabama 36849, United States
| | - Duy Trinh
- Department
of Chemistry, University of Nevada Las Vegas, 4505 South Maryland Parkway, Las Vegas, Nevada 89154, United States
| | - N. Balakrishnan
- Department
of Chemistry, University of Nevada Las Vegas, 4505 South Maryland Parkway, Las Vegas, Nevada 89154, United States
| | - Teck-Ghee Lee
- Department
of Physics, Auburn University, 206 Allison Laboratory, Auburn, Alabama 36849, United States
| | - Robert C. Forrey
- Department
of Physics, Penn State University, Berks Campus, 214 Luerssen
Building, Reading, Pennsylvania 19610, United States
| | - B. H. Yang
- Department
of Physics and Astronomy and Center for Simulational Physics, University of Georgia, Athens, Georgia 30602, United States
| | - P. C. Stancil
- Department
of Physics and Astronomy and Center for Simulational Physics, University of Georgia, Athens, Georgia 30602, United States
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38
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Onvlee J, Vogels SN, Zastrow AV, Parker DH, van de Meerakker SYT. Molecular collisions coming into focus. Phys Chem Chem Phys 2014; 16:15768-79. [DOI: 10.1039/c4cp01519c] [Citation(s) in RCA: 25] [Impact Index Per Article: 2.5] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/21/2022]
Abstract
Control over molecules in a Stark decelerator enables the measurement of diffraction oscillations in NO-atom scattering.
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Affiliation(s)
- Jolijn Onvlee
- Radboud University Nijmegen
- Institute for Molecules and Materials
- 6525 AJ Nijmegen, the Netherlands
| | - Sjoerd N. Vogels
- Radboud University Nijmegen
- Institute for Molecules and Materials
- 6525 AJ Nijmegen, the Netherlands
| | - Alexander von Zastrow
- Radboud University Nijmegen
- Institute for Molecules and Materials
- 6525 AJ Nijmegen, the Netherlands
| | - David H. Parker
- Radboud University Nijmegen
- Institute for Molecules and Materials
- 6525 AJ Nijmegen, the Netherlands
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39
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Tkáč O, Saha AK, Onvlee J, Yang CH, Sarma G, Bishwakarma CK, van de Meerakker SYT, van der Avoird A, Parker DH, Orr-Ewing AJ. State-to-state resolved differential cross sections for rotationally inelastic scattering of ND3with He. Phys Chem Chem Phys 2014; 16:477-88. [DOI: 10.1039/c3cp53550a] [Citation(s) in RCA: 22] [Impact Index Per Article: 2.2] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/21/2022]
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40
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Suleimanov YV, Tscherbul TV, Krems RV. Efficient method for quantum calculations of molecule-molecule scattering properties in a magnetic field. J Chem Phys 2012; 137:024103. [DOI: 10.1063/1.4733288] [Citation(s) in RCA: 20] [Impact Index Per Article: 1.7] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/14/2022] Open
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41
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Chefdeville S, Stoecklin T, Bergeat A, Hickson KM, Naulin C, Costes M. Appearance of low energy resonances in CO-para-H2 inelastic collisions. PHYSICAL REVIEW LETTERS 2012; 109:023201. [PMID: 23030157 DOI: 10.1103/physrevlett.109.023201] [Citation(s) in RCA: 59] [Impact Index Per Article: 4.9] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Received: 04/24/2012] [Indexed: 06/01/2023]
Abstract
We report on crossed-beam experiments and quantum-mechanical calculations performed on the CO(j=0) + H2(j=0) → CO(j=1) + H2(j=0) system. The experimental cross sections determined in the threshold region of the CO(j=0 → j=1) transition at 3.85 cm(-1) show resonance structures in good qualitative agreement with the theoretical ones. These results suggest that the potential energy surface which describes the CO-H2 van der Waals interaction should be reinvestigated for good quantitative agreement.
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Affiliation(s)
- Simon Chefdeville
- Université de Bordeaux, Institut des Sciences Moléculaires, F-33400 Talence, France
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