1
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Plamper D, Vincent A, Fujioka K, Sun R, Weitzel KM. Ion molecule reactions in the HBr + + CH 4 system: a combined experimental and theoretical study. Phys Chem Chem Phys 2024; 26:16732-16746. [PMID: 38814257 DOI: 10.1039/d4cp01121j] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 05/31/2024]
Abstract
Reactions in the system HBr+ + CH4 have been investigated inside a guided ion-beam apparatus under single-collision conditions. The HBr+ is vibrational and rotational state selected in the electronic X2Π1/2 state created by (2+1)-REMPI. Due to the exitation scheme employed different rotational states of the HBr+ are accessible. Four reaction channels have been observed. The cross section, σ, for the exothermic proton transfer channel (PT) decreases with increasing collision energy, steeper than predicted by the Langevin model. The cross section also decreases with increasing rotational energy in the HBr+, with the effect of the rotational energy being stronger than that of translational energy. The cross section for the endothermic charge transfer (CT) increased with increasing collision energy. The energy dependence is well reproduced by a simple line of center (loc) model. Although the bromine transfer (BT) is exothermic the observed cross section increased with increasing collision energy due to an activation barrier on the potential energy surface (PES). Analysis by a modified loc model suggest the relevance of an angle dependence of σ. The cross section for the endothermic hydrogen atom abstraction (HA) exhibits a maximum at 2 eV Ecm. The measured cross sections are rationalized by means of reaction dynamics simulations which show good agreement with the experimental cross sections. The dynamics simulations are carried out with a machine learning potential that is developed and benchmarked with ab initio molecular dynamics simulation. The absolute cross sections predicted by reaction dynamics simulations are well within the same order of magnitude while reproducing the trends over three different collision energies for all four reaction channels. Furthermore, the simulations demonstrate various reaction mechanisms for these reaction channels, including a very interesting HBr+ orientation selectivity for the BT reaction channel.
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Affiliation(s)
- Dominik Plamper
- Philipps-Universität Marburg, Fachbereich Chemie, 35032 Marburg, Germany.
| | - Allen Vincent
- Department of Chemistry, University of Hawai'i at Manoa, Honolulu, Hawaii 96822, USA.
| | - Kazuumi Fujioka
- Department of Chemistry, University of Hawai'i at Manoa, Honolulu, Hawaii 96822, USA.
| | - Rui Sun
- Department of Chemistry, University of Hawai'i at Manoa, Honolulu, Hawaii 96822, USA.
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2
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Mazo-Sevillano PD, Aguado A, Goicoechea JR, Roncero O. Quantum study of the CH3+ photodissociation in full-dimensional neural network potential energy surfaces. J Chem Phys 2024; 160:184307. [PMID: 38738612 DOI: 10.1063/5.0206895] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/05/2024] [Accepted: 04/22/2024] [Indexed: 05/14/2024] Open
Abstract
C H 3 + , a cornerstone intermediate in interstellar chemistry, has recently been detected for the first time by using the James Webb Space Telescope. The photodissociation of this ion is studied here. Accurate explicitly correlated multi-reference configuration interaction ab initio calculations are done, and full-dimensional potential energy surfaces are developed for the three lower electronic states, with a fundamental invariant neural network method. The photodissociation cross section is calculated using a full-dimensional quantum wave packet method in heliocentric Radau coordinates. The wave packet is represented in angular and radial grids, allowing us to reduce the number of points physically accessible, requiring to push up the spurious states appearing when evaluating the angular kinetic terms, through projection technique. The photodissociation spectra, when employed in astrochemical models to simulate the conditions of the Orion bar, result in a lesser destruction of CH3+ compared to that obtained when utilizing the recommended values in the kinetic database for astrochemistry.
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Affiliation(s)
- Pablo Del Mazo-Sevillano
- Unidad Asociada UAM-IFF-CSIC, Departamento de Química Física Aplicada, Facultad de Ciencias M-14, Universidad Autónoma de Madrid, 28049 Madrid, Spain
| | - Alfredo Aguado
- Unidad Asociada UAM-IFF-CSIC, Departamento de Química Física Aplicada, Facultad de Ciencias M-14, Universidad Autónoma de Madrid, 28049 Madrid, Spain
| | - Javier R Goicoechea
- Instituto de Física Fundamental (IFF-CSIC), C.S.I.C., Serrano 123, 28006 Madrid, Spain
| | - Octavio Roncero
- Instituto de Física Fundamental (IFF-CSIC), C.S.I.C., Serrano 123, 28006 Madrid, Spain
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3
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Vásquez-Espinal A, Pino-Rios R. Strong carbon - noble gas covalent bond and fluxionality in hypercoordinate compounds. Phys Chem Chem Phys 2023; 25:27468-27474. [PMID: 37800185 DOI: 10.1039/d3cp03576j] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/07/2023]
Abstract
Thermodynamic, kinetic, and chemical bonding analysis at the coupled cluster level has been carried out for a series of hypercoordinated carbon compounds with formula CH4Ng2+ (Ng = He-Rn). Results show that these compounds could be stable at room temperature and Born-Oppenheimer molecular dynamics simulations (BOMD) in conjunction with activation energies indicate high kinetic stability. In addition, all chemical bonding descriptors agree with a strong C-Ng covalent bond and a bonding pattern similar to that of CH5+. Finally, BOMD simulations showed that these compounds are fluxional, with a continuous formation/breaking of H-H and C-H bonds. To the best of the authors' knowledge, these results represent the first series of fluxional compounds possessing a covalent bond between a main group element and a noble gas atom.
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Affiliation(s)
- Alejandro Vásquez-Espinal
- Química y Farmacia, Facultad de Ciencias de la Salud, Universidad Arturo Prat. Casilla 121, Iquique 1100000, Chile.
| | - Ricardo Pino-Rios
- Química y Farmacia, Facultad de Ciencias de la Salud, Universidad Arturo Prat. Casilla 121, Iquique 1100000, Chile.
- Instituto de Estudios de la Salud, Universidad Arturo Prat, Iquique, 1100000, Chile
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4
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Simkó I, Schran C, Brieuc F, Fábri C, Asvany O, Schlemmer S, Marx D, Császár AG. Quantum Nuclear Delocalization and its Rovibrational Fingerprints. Angew Chem Int Ed Engl 2023; 62:e202306744. [PMID: 37561837 DOI: 10.1002/anie.202306744] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/15/2023] [Revised: 08/07/2023] [Accepted: 08/10/2023] [Indexed: 08/12/2023]
Abstract
Quantum mechanics dictates that nuclei must undergo some delocalization. In this work, emergence of quantum nuclear delocalization and its rovibrational fingerprints are discussed for the case of the van der Waals complexHHe 3 + ${{\rm{HHe}}_3^ + }$ . The equilibrium structure ofHHe 3 + ${{\rm{HHe}}_3^ + }$ is planar and T-shaped, one He atom solvating the quasi-linear He-H+ -He core. The dynamical structure ofHHe 3 + ${{\rm{HHe}}_3^ + }$ , in all of its bound states, is fundamentally different. As revealed by spatial distribution functions and nuclear densities, during the vibrations of the molecule the solvating He is not restricted to be in the plane defined by the instantaneously bentHHe 2 + ${{\rm{HHe}}_2^ + }$ chomophore, but freely orbits the central proton, forming a three-dimensional torus around theHHe 2 + ${{\rm{HHe}}_2^ + }$ chromophore. This quantum delocalization is observed for all vibrational states, the type of vibrational excitation being reflected in the topology of the nodal surfaces in the nuclear densities, showing, for example, that intramolecular bending involves excitation along the circumference of the torus.
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Affiliation(s)
- Irén Simkó
- Laboratory of Molecular Structure and Dynamics, Institute of Chemistry, ELTE Eötvös Loránd University, H-1117, Budapest, Pázmány Péter sétány 1/A, Hungary
- MTA-ELTE Complex Chemical Systems Research Group, H-1117, Budapest, Pázmány Péter sétány 1/A, Hungary
- Hevesy György PhD School of Chemistry, ELTE Eötvös Loránd University, H-1117, Budapest, Pázmány Péter sétány 1/A, Hungary
| | - Christoph Schran
- Lehrstuhl für Theoretische Chemie, Ruhr-Universität Bochum, 44780, Bochum, Germany
- Present address: Yusuf Hamied Department of Chemistry, University of Cambridge, Lensfield Road, Cambridge, CB2 1EW, UK
| | - Fabien Brieuc
- Lehrstuhl für Theoretische Chemie, Ruhr-Universität Bochum, 44780, Bochum, Germany
- Present address: Laboratoire Matière en Conditions Extrêmes, Université Paris-Saclay, CEA, DAM, DIF, 91297, Arpajon, France
| | - Csaba Fábri
- MTA-ELTE Complex Chemical Systems Research Group, H-1117, Budapest, Pázmány Péter sétány 1/A, Hungary
| | - Oskar Asvany
- I. Physikalisches Institut, Universität zu Köln, Zülpicher Str. 77, 50937, Köln, Germany
| | - Stephan Schlemmer
- I. Physikalisches Institut, Universität zu Köln, Zülpicher Str. 77, 50937, Köln, Germany
| | - Dominik Marx
- Lehrstuhl für Theoretische Chemie, Ruhr-Universität Bochum, 44780, Bochum, Germany
| | - Attila G Császár
- Laboratory of Molecular Structure and Dynamics, Institute of Chemistry, ELTE Eötvös Loránd University, H-1117, Budapest, Pázmány Péter sétány 1/A, Hungary
- MTA-ELTE Complex Chemical Systems Research Group, H-1117, Budapest, Pázmány Péter sétány 1/A, Hungary
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5
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Moonkaen P, Finney JM, McCoy AB. Isotope Effects on Ground and Excited States of Ethyl Cation, H +(C 2H 4). J Phys Chem A 2023; 127:1196-1205. [PMID: 36705480 DOI: 10.1021/acs.jpca.2c07334] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/28/2023]
Abstract
The structure and spectra of ethyl cation, H+(C2H4), and its deuterated analogues are investigated using diffusion Monte Carlo (DMC). These calculations all show that the ground state wave function for H+(C2H4) is localized near the minimum energy configuration in which the excess proton is in a bridging configuration, although the amplitude of the vibrational motions of the bridging proton is large. Deuteration of the bridging proton reduces the amplitude of this motion, while deuteration of only the ethylenic hydrogen atoms in H+(C2D4) has little effect on the amplitude of the motion of the bridging proton. Excited states that are accessed by spectroscopically observed transitions in H+(C2H4) are calculated using fixed-node DMC. The calculated and measured frequencies for the states with one quantum of excitation in the ethylenic CH stretching vibrations show good agreement. We also explore the excited state with one quantum of excitation in the proton transfer vibration of the bridging proton and obtain a frequency of 616 cm-1 for H+(C2H4). This frequency increases to 629 cm-1 in H+(C2D4). Deuteration decreases this frequency to 491 and 495 cm-1 in D+(C2H4) and D+(C2D4), respectively. The effects of partial deuteration on the frequencies of the CH stretching vibrations, and the corresponding probability amplitudes are also explored. Finally, we report the vibrationally averaged rotational constants for the four isotopologues of ethyl cation considered in this study.
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Affiliation(s)
- Pattarapon Moonkaen
- Department of Chemistry, University of Washington, Seattle, Washington 98195, United States
| | - Jacob M Finney
- Department of Chemistry, University of Washington, Seattle, Washington 98195, United States
| | - Anne B McCoy
- Department of Chemistry, University of Washington, Seattle, Washington 98195, United States
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6
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Jin J, Wulf T, Jorewitz M, Heine T, Asmis KR. Vibrational spectroscopy of Cu +(H 2) 4: about anharmonicity and fluxionality. Phys Chem Chem Phys 2023; 25:5262-5270. [PMID: 36723211 DOI: 10.1039/d2cp05802b] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 02/02/2023]
Abstract
The vibrational spectra of the copper(I) cation-dihydrogen complexes Cu+(H2)4, Cu+(D2)4 and Cu+(D2)3H2 are studied using cryogenic ion trap vibrational spectroscopy in combination with quantum chemical calculations. The infrared photodissociation (IRPD) spectra (2500-7300 cm-1) are assigned based on a comparison to IR spectra calculated using vibrational second-order perturbation theory (VPT2). The IRPD spectra exhibit ≈60 cm-1 broad bands that lack rotational resolution, indicative of rather floppy complexes even at an ion trap temperature of 10 K. The observed vibrational features are assigned to the excitations of dihydrogen stretching fundamentals, combination bands of these fundamentals with low energy excitations as well as overtone excitations of a minimum-energy structure with Cs symmetry. The three distinct dihydrogen positions present in the structure can interconvert via pseudorotations with energy barriers less than 10 cm-1, far below the zero-point vibrational energy. Ab initio Born-Oppenheimer molecular dynamics (BOMD) simulations confirm the fluxional behavior of these complexes and yield an upper limit for the timeframe of the pseudorotation on the order of 10 ps. For Cu+(D2)3H2, the H2 and D2 loss channels yield different IRPD spectra indicating non-ergodic behavior.
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Affiliation(s)
- Jiaye Jin
- Wilhelm-Ostwald-Institut für Physikalische und Theoretisch Chemie, Universität Leipzig, Linnéstr. 2, 04103, Leipzig, Germany.
| | - Toshiki Wulf
- Wilhelm-Ostwald-Institut für Physikalische und Theoretisch Chemie, Universität Leipzig, Linnéstr. 2, 04103, Leipzig, Germany. .,Institute of Resource Ecology, Research Site Leipzig, Helmholtz-Zentrum Dresden-Rossendorf, Permoserstr. 15, 04318, Leipzig, Germany.,Faculty of Chemistry and Food Chemistry, School of Science, TU Dresden, 01062, Dresden, Germany.
| | - Marcel Jorewitz
- Wilhelm-Ostwald-Institut für Physikalische und Theoretisch Chemie, Universität Leipzig, Linnéstr. 2, 04103, Leipzig, Germany.
| | - Thomas Heine
- Institute of Resource Ecology, Research Site Leipzig, Helmholtz-Zentrum Dresden-Rossendorf, Permoserstr. 15, 04318, Leipzig, Germany.,Faculty of Chemistry and Food Chemistry, School of Science, TU Dresden, 01062, Dresden, Germany.
| | - Knut R Asmis
- Wilhelm-Ostwald-Institut für Physikalische und Theoretisch Chemie, Universität Leipzig, Linnéstr. 2, 04103, Leipzig, Germany.
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7
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Simkó I, Fábri C, Császár AG. Quantum-Chemical and Quantum-Graph Models of the Dynamical Structure of CH 5. J Chem Theory Comput 2023; 19:42-50. [PMID: 36534596 DOI: 10.1021/acs.jctc.2c00991] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/24/2022]
Abstract
Experimental and computational results about the structure, dynamics, and rovibrational spectra of protonated methane have challenged a considerable number of traditional chemical concepts. Hereby theoretical and computational results are provided about the dynamical structure of CH5+. It is shown that the ground vibrational state investigated thus far by computations, forbidden by nuclear-spin statistics, has a structure similar to the first allowed vibrational state and, in fact, the structures of all vibrational states significantly below 200 cm-1 are highly similar. Spatial delocalization of the nuclei, determined by nuclear densities computed from accurate variational vibrational wave functions, turns out to be limited when viewed in the body-fixed frame, confirming that the effective structure of CH5+ is well described as a CH3+ tripod with a H2 unit on top of it. The interesting and unusual qualitative aspects of the sophisticated state-dependent variational results receive full explanation via simple quantum-graph models.
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Affiliation(s)
- Irén Simkó
- Hevesy György PhD School of Chemistry, ELTE Eötvös Loránd University, Pázmány Péter sétány 1/A, H-1117 Budapest, Hungary.,Laboratory of Molecular Structure and Dynamics, Institute of Chemistry, ELTE Eötvös Loránd University, Pázmány Péter sétány 1/A, H-1117 Budapest, Hungary.,MTA-ELTE Complex Chemical Systems Research Group, P.O. Box 32, H-1518 Budapest 112, Hungary
| | - Csaba Fábri
- MTA-ELTE Complex Chemical Systems Research Group, P.O. Box 32, H-1518 Budapest 112, Hungary
| | - Attila G Császár
- Laboratory of Molecular Structure and Dynamics, Institute of Chemistry, ELTE Eötvös Loránd University, Pázmány Péter sétány 1/A, H-1117 Budapest, Hungary.,MTA-ELTE Complex Chemical Systems Research Group, P.O. Box 32, H-1518 Budapest 112, Hungary
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8
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Pentacoordinate Carbon Atoms in a Ferrocene Dication Derivative—[Fe(Si2-η5-C5H2)2]2+. CHEMISTRY 2022. [DOI: 10.3390/chemistry4040074] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/16/2022] Open
Abstract
Pentacoordinate carbon atoms are theoretically predicted here in a ferrocene dication derivative in the eclipsed-(1; C2v), gauche-(2; C2) and staggered-[Fe(Si2-η5-C5H2)2]2+(3; C2h) forms for the first time. Energetically, the relative energy gaps for 2 and 3 range from −3.06 to 16.74 and −2.78 to 40.34 kJ mol−1, respectively, when compared to the singlet electronic state of 1 at different levels. The planar tetracoordinate carbon (ptC) atom in the ligand Si2C5H2 becomes a pentacoordinate carbon upon complexation. The ligand with a ptC atom was predicted to be both a thermodynamically and kinetically stable molecule by some of us in our earlier theoretical works. Natural bond orbital and adaptive natural density partitioning analyses confirm the pentacoordinate nature of carbon in these three complexes (1–3). Although they are hypothetical at the moment, they support the idea of “hypercoordinate metallocenes” within organometallic chemistry. Moreover, ab initio molecular dynamics simulations carried out at 298 K temperature for 2000 fs suggest that these molecules are kinetically stable.
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Abstract
A few months before the COVID-19 pandemic, Pierre Vogel and Kendall N. Houk published with a new textbook Wiley-VCH, “Organic Chemistry: Theory, Reactivity, and Mechanisms in Modern Synthesis”, with a foreword from the late Roberts H. Grubbs. The book demonstrates how catalytic processes dominate all fields of modern organic chemistry and synthesis, and how invention combines thermodynamics, kinetics, spectroscopy, quantum mechanics, and thermochemical data libraries. Here, the authors present a few case studies that should be of interest to teachers, practitioners of organic and organometallic chemistry, and the engineers of molecules. The Vogel–Houk book is both textbook and reference manual; it provides a modern way to think about chemical reactivity and a powerful toolbox to inventors of new reactions and new procedures.
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10
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Fletcher T, Zhu A, Lawrence JE, Manolopoulos DE. Fast quasi-centroid molecular dynamics. J Chem Phys 2021; 155:231101. [PMID: 34937347 DOI: 10.1063/5.0076704] [Citation(s) in RCA: 7] [Impact Index Per Article: 2.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/14/2022] Open
Abstract
We describe a fast implementation of the quasi-centroid molecular dynamics (QCMD) method in which the quasi-centroid potential of mean force is approximated as a separable correction to the classical interaction potential. This correction is obtained by first calculating quasi-centroid radial and angular distribution functions in a short path integral molecular dynamics simulation and then using iterative Boltzmann inversion to obtain an effective classical potential that reproduces these distribution functions in a classical NVT simulation. We illustrate this approach with example applications to the vibrational spectra of gas phase molecules, obtaining excellent agreement with QCMD reference calculations for water and ammonia and good agreement with the quantum mechanical vibrational spectrum of methane.
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Affiliation(s)
- Theo Fletcher
- Physical and Theoretical Chemistry Laboratory, Department of Chemistry, University of Oxford, South Parks Road, Oxford OX1 3QZ, United Kingdom
| | - Andrew Zhu
- Physical and Theoretical Chemistry Laboratory, Department of Chemistry, University of Oxford, South Parks Road, Oxford OX1 3QZ, United Kingdom
| | - Joseph E Lawrence
- Laboratory of Physical Chemistry, ETH Zürich, 8093 Zürich, Switzerland
| | - David E Manolopoulos
- Physical and Theoretical Chemistry Laboratory, Department of Chemistry, University of Oxford, South Parks Road, Oxford OX1 3QZ, United Kingdom
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11
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Davies JA, Yang S, Ellis AM. Infrared spectra of carbocations and CH 4+ in helium. Phys Chem Chem Phys 2021; 23:27449-27459. [PMID: 34870649 DOI: 10.1039/d1cp03138d] [Citation(s) in RCA: 3] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/21/2022]
Abstract
Infrared (IR) spectra of several hydrocarbon cations are reported, namely CH3+, CH4+, CH5+, CH5+(CH4) and C2H5+. The spectra were generated from weakly-bound helium-cation complexes formed by electron ionization of helium nanodroplets doped with a neutral hydrocarbon precursor. Spectroscopic transitions were registered by photoexcitation of the complexes coupled with mass spectrometric detection of the bare ions. For CH3+, we provide evidence showing that the helium-bound complexes contain 10-20 helium atoms (on average) and have a rotational temperature of ∼5 K. We show that this technique is well-suited to the study of highly symmetric or fluxional ionic species, as these intrinsic properties are preserved in the helium environment. This is in contrast to conventional tagging methods that use a single atom or molecule, which can change the point group or rigidity of the core ion and therefore the spectral profile. We demonstrate this for the highly fluxional molecular ion CH5+, whose spectrum in the current study matches that of the gas phase ion, whereas the fluxionality is lost when a methane tag is added. Finally, we present the first IR spectrum of methane cation, CH4+. The spectrum of this fundamental organic ion shows CH stretching bands consistent with a non-tetrahedral structure, a consequence of Jahn-Teller distortion.
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Affiliation(s)
- Julia A Davies
- Department of Chemistry, University of Leicester, University Road, Leicester, LE1 7RH, UK.
| | - Shengfu Yang
- Department of Chemistry, University of Leicester, University Road, Leicester, LE1 7RH, UK.
| | - Andrew M Ellis
- Department of Chemistry, University of Leicester, University Road, Leicester, LE1 7RH, UK.
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12
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Asvany O, Schlemmer S. Rotational action spectroscopy of trapped molecular ions. Phys Chem Chem Phys 2021; 23:26602-26622. [PMID: 34817492 DOI: 10.1039/d1cp03975j] [Citation(s) in RCA: 10] [Impact Index Per Article: 3.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/03/2023]
Abstract
Rotational action spectroscopy is an experimental method in which rotational spectra of molecules, typically in the microwave to sub-mm-wave domain of the electromagnetic spectrum (∼1-1000 GHz), are recorded by action spectroscopy. Action spectroscopy means that the spectrum is recorded not by detecting the absorption of light by the molecules, but by the action of the light on the molecules, e.g., photon-induced dissociation of a chemical bond, a photon-triggered reaction, or photodetachment of an electron. Typically, such experiments are performed on molecular ions, which can be well controlled and mass-selected by guiding and storage techniques. Though coming with many advantages, the application of action schemes to rotational spectroscopy was hampered for a long time by the small energy content of a corresponding photon. Therefore, the first rotational action spectroscopic methods emerged only about one decade ago. Today, there exists a toolbox full of different rotational action spectroscopic schemes which are summarized in this review.
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Affiliation(s)
- Oskar Asvany
- I. Physikalisches Institut, Universität zu Köln, Zülpicher Str. 77, 50937 Köln, Germany.
| | - Stephan Schlemmer
- I. Physikalisches Institut, Universität zu Köln, Zülpicher Str. 77, 50937 Köln, Germany.
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13
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Erukala S, Feinberg A, Singh A, Vilesov AF. Infrared spectroscopy of carbocations upon electron ionization of ethylene in helium nanodroplets. J Chem Phys 2021; 155:084306. [PMID: 34470362 DOI: 10.1063/5.0062171] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/14/2022] Open
Abstract
The electron impact ionization of helium droplets doped with ethylene molecules and clusters yields diverse CXHY + cations embedded in the droplets. The ionization primarily produces C2H2 +, C2H3 +, C2H4 +, and CH2 +, whereas larger carbocations are produced upon the reactions of the primary ions with ethylene molecules. The vibrational excitation of the cations leads to the release of bare cations and cations with a few helium atoms attached. The laser excitation spectra of the embedded cations show well resolved vibrational bands with a few wavenumber widths-an order of magnitude less than those previously obtained in solid matrices or molecular beams by tagging techniques. Comparison with the previous studies of free and tagged CH2 +, CH3 +, C2H2 +, C2H3 +, and C2H4 + cations shows that the helium matrix typically introduces a shift in the vibrational frequencies of less than about 20 cm-1, enabling direct comparisons with the results of quantum chemical calculations for structure determination. This work demonstrates a facile technique for the production and spectroscopic study of diverse carbocations, which act as important intermediates in gas and condensed phases.
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Affiliation(s)
- Swetha Erukala
- Department of Chemistry, University of Southern California, Los Angeles, California 90089, USA
| | - Alexandra Feinberg
- Department of Chemistry, University of Southern California, Los Angeles, California 90089, USA
| | - Amandeep Singh
- Department of Chemistry, University of Southern California, Los Angeles, California 90089, USA
| | - Andrey F Vilesov
- Department of Chemistry, University of Southern California, Los Angeles, California 90089, USA
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14
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Rawlinson JI, Fábri C, Császár AG. Exactly solvable 1D model explains the low-energy vibrational level structure of protonated methane. Chem Commun (Camb) 2021; 57:4827-4830. [PMID: 33861262 DOI: 10.1039/d1cc01214b] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/11/2022]
Abstract
A new one-dimensional model is proposed for the low-energy vibrational quantum dynamics of CH5+ based on the motion of an effective particle confined to a 60-vertex graph Γ60 with a single edge length parameter. Within this model, the quantum states of CH5+ are obtained in analytic form and are related to combinatorial properties of Γ60. The bipartite structure of Γ60 gives a simple explanation for curious symmetries observed in numerically exact variational calculations on CH5+.
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Affiliation(s)
| | - Csaba Fábri
- Laboratory of Molecular Structure and Dynamics, Institute of Chemistry, ELTE Eötvös Loránd University, Pázmány Péter sétány 1/A, Budapest H-1117, Hungary and MTA-ELTE Complex Chemical Systems Research Group, P.O. Box 32, Budapest 112 H-1518, Hungary
| | - Attila G Császár
- Laboratory of Molecular Structure and Dynamics, Institute of Chemistry, ELTE Eötvös Loránd University, Pázmány Péter sétány 1/A, Budapest H-1117, Hungary and MTA-ELTE Complex Chemical Systems Research Group, P.O. Box 32, Budapest 112 H-1518, Hungary
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15
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A matrix isolation and Ab initio study on C2H6…HCN complex: An unusual example of hydrogen bonding. J Mol Struct 2021. [DOI: 10.1016/j.molstruc.2021.129910] [Citation(s) in RCA: 3] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/19/2022]
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16
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Bauer B, Bravyi S, Motta M, Chan GKL. Quantum Algorithms for Quantum Chemistry and Quantum Materials Science. Chem Rev 2020; 120:12685-12717. [DOI: 10.1021/acs.chemrev.9b00829] [Citation(s) in RCA: 134] [Impact Index Per Article: 33.5] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/23/2023]
Affiliation(s)
- Bela Bauer
- Microsoft Quantum, Station Q, University of California
, Santa Barbara, California 93106, United States
| | - Sergey Bravyi
- IBM Quantum, IBM T. J. Watson Research Center
, Yorktown Heights, New York 10598, United States
| | - Mario Motta
- IBM Quantum, IBM Research Almaden
, San Jose, California 95120, United States
| | - Garnet Kin-Lic Chan
- Division of Chemistry and Chemical Engineering, California Institute of Technology
, Pasadena, California 91125, United States
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17
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Boutwell D, Okere O, Omodemi O, Toledo A, Barrios A, Olocha M, Kaledin M. Analysis of the Proton Transfer Bands in the Infrared Spectra of Linear N 2H +···OC and N 2D +···OC Complexes Using Electric Field-Driven Classical Trajectories. J Phys Chem A 2020; 124:7549-7558. [PMID: 32808782 DOI: 10.1021/acs.jpca.0c06756] [Citation(s) in RCA: 4] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/28/2022]
Abstract
In this work, we describe ab initio calculations and assignment of infrared (IR) spectra of hydrogen-bonded ion-molecular complexes that involve a fluxional proton: the linear N2H+···OC and N2D+···OC complexes. Given the challenges of describing fluxional proton dynamics and especially its IR activity, we use electric field-driven classical trajectories, i.e., the driven molecular dynamics (DMD) method that was developed by us in recent years and for similar applications, in conjunction with high-level electronic structure theory. Namely, we present a modified and a numerically efficient implementation of DMD specifically for direct (or "on the fly") calculations, which we carry out at the MP2-F12/AVDZ level of theory for the potential energy surface (PES) and MP2/AVDZ for the dipole moment surfaces (DMSs). Detailed analysis of the PES, DMS, and the time-dependence of the first derivative of the DMS, referred to as the driving force, for the highly fluxional vibrations involving H+/D+ revealed that the strongly non-harmonic PES and non-linear DMS yield remarkably complex vibrational spectra. Interestingly, the classical trajectories reveal a doublet in the proton transfer part of the spectrum with the two peaks at 1800 and 1980 cm-1. We find that their shared intensity is due to a Fermi-like resonance interaction, within the classical limit, of the H+ parallel stretch fundamental and an H+ perpendicular bending overtone. This doublet is also observed in the deuterated species at 1360 and 1460 cm-1.
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Affiliation(s)
- Dalton Boutwell
- Department of Chemistry & Biochemistry, Kennesaw State University, 370 Paulding Ave NW, Box # 1203, Kennesaw, Georgia 30144, United States
| | - Onyinye Okere
- Department of Chemistry & Biochemistry, Kennesaw State University, 370 Paulding Ave NW, Box # 1203, Kennesaw, Georgia 30144, United States
| | - Oluwaseun Omodemi
- Department of Chemistry & Biochemistry, Kennesaw State University, 370 Paulding Ave NW, Box # 1203, Kennesaw, Georgia 30144, United States
| | - Alexander Toledo
- Department of Chemistry & Biochemistry, Kennesaw State University, 370 Paulding Ave NW, Box # 1203, Kennesaw, Georgia 30144, United States
| | - Antonio Barrios
- Department of Chemistry & Biochemistry, Kennesaw State University, 370 Paulding Ave NW, Box # 1203, Kennesaw, Georgia 30144, United States
| | - Monique Olocha
- Department of Chemistry & Biochemistry, Kennesaw State University, 370 Paulding Ave NW, Box # 1203, Kennesaw, Georgia 30144, United States
| | - Martina Kaledin
- Department of Chemistry & Biochemistry, Kennesaw State University, 370 Paulding Ave NW, Box # 1203, Kennesaw, Georgia 30144, United States
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18
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19
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Probing the Fluxional Bonding Nature of Rapid Cope rearrangements in Bullvalene C 10H 10 and Its Analogs C 8H 8, C 9H 10, and C 8BH 9. Sci Rep 2019; 9:17074. [PMID: 31745136 PMCID: PMC6864245 DOI: 10.1038/s41598-019-53488-5] [Citation(s) in RCA: 6] [Impact Index Per Article: 1.2] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/08/2019] [Accepted: 10/31/2019] [Indexed: 11/18/2022] Open
Abstract
Bullvalene C10H10 and its analogs semibullvalene C8H8, barbaralane C9H10, and 9-Borabarbaralane C8BH9 are prototypical fluxional molecules with rapid Cope rearrangements at finite temperatures. Detailed bonding analyses performed in this work reveal the existence of two fluxional π-bonds (2 2c-2e π → 2 3c-2e π → 2 2c-2e π) and one fluxional σ-bond (1 2c-2e σ → 1 4c-2e σ → 1 2c-2e σ) in their ground states and transition states, unveiling the universal π + σ double fluxional bonding nature of these fluctuating cage-like species. The highest occupied natural bond orbitals (HONBOs) turn out to be typical fluxional bonds dominating the dynamics of the systems. The 13C-NMR and 1H-NMR shielding tensors and chemical shifts of the model compound C8BH9 are computationally predicted to facilitate future experiments.
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20
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Császár AG, Fábri C, Sarka J. Quasistructural molecules. WILEY INTERDISCIPLINARY REVIEWS-COMPUTATIONAL MOLECULAR SCIENCE 2019. [DOI: 10.1002/wcms.1432] [Citation(s) in RCA: 11] [Impact Index Per Article: 2.2] [Reference Citation Analysis] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 11/10/2022]
Affiliation(s)
- Attila G. Császár
- Laboratory of Molecular Structure and Dynamics, Institute of Chemistry ELTE Eötvös Loránd University Budapest Hungary
- MTA‐ELTE Complex Chemical Systems Research Group Budapest Hungary
| | - Csaba Fábri
- Laboratory of Molecular Structure and Dynamics, Institute of Chemistry ELTE Eötvös Loránd University Budapest Hungary
- MTA‐ELTE Complex Chemical Systems Research Group Budapest Hungary
| | - János Sarka
- Department of Chemistry and Biochemistry Texas Tech University Lubbock Texas USA
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21
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Zeng HJ, Yang N, Johnson MA. Introductory lecture: advances in ion spectroscopy: from astrophysics to biology. Faraday Discuss 2019; 217:8-33. [PMID: 31094388 DOI: 10.1039/c9fd00030e] [Citation(s) in RCA: 13] [Impact Index Per Article: 2.6] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/23/2022]
Abstract
This introduction provides a historical context for the development of ion spectroscopy over the past half century by following the evolution of experimental methods to the present state-of-the-art. Rather than attempt a comprehensive review, we focus on how early work on small ions, carried out with fluorescence, direct absorption, and photoelectron spectroscopy, evolved into powerful technologies that can now address complex chemical problems ranging from catalysis to biophysics. One of these developments is the incorporation of cooling and temperature control to enable the general application of "messenger tagging" vibrational spectroscopy, first carried out using ionized supersonic jets and then with buffer gas cooling in radiofrequency ion traps. Some key advances in the application of time-resolved pump-probe techniques to follow ultrafast dynamics are also discussed, as are significant benchmarks in the refinement of ion mobility to allow spectroscopic investigation of large biopolymers with well-defined shapes. We close with a few remarks on challenges and opportunities to explore molecular level mechanics that drive macroscopic behavior.
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Affiliation(s)
- Helen J Zeng
- Sterling Chemistry Laboratory, Yale University, New Haven, CT 06520, USA.
| | - Nan Yang
- Sterling Chemistry Laboratory, Yale University, New Haven, CT 06520, USA.
| | - Mark A Johnson
- Sterling Chemistry Laboratory, Yale University, New Haven, CT 06520, USA.
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22
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Fore ME, McCoy AB. Statistical Analysis of the Effect of Deuteration on Quantum Delocalization in CH5+. J Phys Chem A 2019; 123:4623-4631. [DOI: 10.1021/acs.jpca.9b02685] [Citation(s) in RCA: 4] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/29/2022]
Affiliation(s)
- Meredith E. Fore
- Department of Chemistry, University of Washington, Seattle, Washington 98195, United States
| | - Anne B. McCoy
- Department of Chemistry, University of Washington, Seattle, Washington 98195, United States
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23
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Yan M, Li HR, Tian XX, Mu YW, Lu HG, Li SD. Fluxional bonds in quasi-planar B182− and half-sandwich MB18− (M = K, Rb, and Cs). J Comput Chem 2019; 40:1227-1232. [DOI: 10.1002/jcc.25782] [Citation(s) in RCA: 6] [Impact Index Per Article: 1.2] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/02/2018] [Revised: 12/28/2018] [Accepted: 01/02/2019] [Indexed: 11/06/2022]
Affiliation(s)
- Miao Yan
- Institute of Molecular Science, Shanxi University; Taiyuan 030006 China
| | - Hai-Ru Li
- Institute of Molecular Science, Shanxi University; Taiyuan 030006 China
| | - Xin-Xin Tian
- Institute of Molecular Science, Shanxi University; Taiyuan 030006 China
| | - Yue-Wen Mu
- Institute of Molecular Science, Shanxi University; Taiyuan 030006 China
| | - Hai-Gang Lu
- Institute of Molecular Science, Shanxi University; Taiyuan 030006 China
| | - Si-Dian Li
- Institute of Molecular Science, Shanxi University; Taiyuan 030006 China
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24
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Gnanasekar SP, Arunan E. Inter/Intramolecular Bonds in TH5+ (T = C/Si/Ge): H2 as Tetrel Bond Acceptor and the Uniqueness of Carbon Bonds. J Phys Chem A 2018; 123:1168-1176. [DOI: 10.1021/acs.jpca.8b09778] [Citation(s) in RCA: 22] [Impact Index Per Article: 3.7] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/28/2022]
Affiliation(s)
- Sharon Priya Gnanasekar
- Department of Inorganic and Physical Chemistry, Indian Institute of Science, Bangalore 560012, India
| | - Elangannan Arunan
- Department of Inorganic and Physical Chemistry, Indian Institute of Science, Bangalore 560012, India
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25
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Uhl F, Marx D. Helium Tagging of Protonated Methane in Messenger Spectroscopy: Does It Interfere with the Fluxionality of CH5
+
? Angew Chem Int Ed Engl 2018. [DOI: 10.1002/ange.201808531] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.2] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/18/2023]
Affiliation(s)
- Felix Uhl
- Lehrstuhl für Theoretische Chemie; Ruhr-Universität Bochum; 44780 Bochum Germany
| | - Dominik Marx
- Lehrstuhl für Theoretische Chemie; Ruhr-Universität Bochum; 44780 Bochum Germany
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26
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Uhl F, Marx D. Helium Tagging of Protonated Methane in Messenger Spectroscopy: Does It Interfere with the Fluxionality of CH5
+
? Angew Chem Int Ed Engl 2018; 57:14792-14795. [DOI: 10.1002/anie.201808531] [Citation(s) in RCA: 9] [Impact Index Per Article: 1.5] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/25/2018] [Indexed: 01/18/2023]
Affiliation(s)
- Felix Uhl
- Lehrstuhl für Theoretische Chemie; Ruhr-Universität Bochum; 44780 Bochum Germany
| | - Dominik Marx
- Lehrstuhl für Theoretische Chemie; Ruhr-Universität Bochum; 44780 Bochum Germany
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27
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28
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Esser A, Forbert H, Marx D. Tagging effects on the mid-infrared spectrum of microsolvated protonated methane. Chem Sci 2018; 9:1560-1573. [PMID: 29675201 PMCID: PMC5890325 DOI: 10.1039/c7sc04040g] [Citation(s) in RCA: 8] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/14/2017] [Accepted: 12/21/2017] [Indexed: 11/21/2022] Open
Abstract
Although bare protonated methane is by now essentially understood at the level of intramolecular large-amplitude motion, scrambling dynamics and broadband vibrational spectra, the microsolvated species still offer plenty of challenges. One aspect is the effect of the attached solvent molecules on the infrared absorption spectra of microsolvated CH5+ complexes compared to the bare parent molecule. In this study we analyze, based on ab initio molecular dynamics simulations, protonated methane molecules that have been microsolvated with up to three hydrogen molecules, i.e. CH5+·(H2) n . In particular, upon introducing a novel multi-channel maximum entropy methodology described herein, we are able to decompose the infrared spectra of these weakly-bound complexes in the frequency window from 1000 to 4500 cm-1 into additive single mode contributions. Detailed comparisons to the bare CH5+ parent reveal that these perturbed modes encode distinct features that depend on the exact microsolvation pattern. Beyond the specific case, such understanding is relevant to assess tagging artifacts in vibrational spectra of parent molecules based on messenger predissociation action spectroscopy.
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Affiliation(s)
- Alexander Esser
- Lehrstuhl für Theoretische Chemie , Ruhr-Universität Bochum , 44780 Bochum , Germany
| | - Harald Forbert
- Center for Solvation Science ZEMOS , Ruhr-Universität Bochum , 44780 Bochum , Germany
| | - Dominik Marx
- Lehrstuhl für Theoretische Chemie , Ruhr-Universität Bochum , 44780 Bochum , Germany
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29
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Fábri C, Császár AG. Vibrational quantum graphs and their application to the quantum dynamics of CH5+. Phys Chem Chem Phys 2018; 20:16913-16917. [DOI: 10.1039/c8cp03019g] [Citation(s) in RCA: 9] [Impact Index Per Article: 1.5] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/21/2022]
Abstract
The first application of quantum-graph theory to molecular vibrations helps understand the low-energy vibrational quantum dynamics of CH5+.
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Affiliation(s)
- Csaba Fábri
- Laboratory of Molecular Structure and Dynamics
- Institute of Chemistry
- Eötvös Loránd University
- H-1117 Budapest
- Hungary
| | - Attila G. Császár
- Laboratory of Molecular Structure and Dynamics
- Institute of Chemistry
- Eötvös Loránd University
- H-1117 Budapest
- Hungary
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30
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Fábri C, Quack M, Császár AG. On the use of nonrigid-molecular symmetry in nuclear motion computations employing a discrete variable representation: A case study of the bending energy levels of C H 5 +. J Chem Phys 2017; 147:134101. [DOI: 10.1063/1.4990297] [Citation(s) in RCA: 24] [Impact Index Per Article: 3.4] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/14/2022] Open
Affiliation(s)
- Csaba Fábri
- Laboratory of Molecular Structure and Dynamics, Institute of Chemistry, Eötvös University, Pázmány Péter sétány 1/A, H-1117 Budapest, Hungary
- Physical Chemistry, ETH Zürich, CH-8093 Zürich, Switzerland
| | - Martin Quack
- Physical Chemistry, ETH Zürich, CH-8093 Zürich, Switzerland
| | - Attila G. Császár
- Laboratory of Molecular Structure and Dynamics, Institute of Chemistry, Eötvös University, Pázmány Péter sétány 1/A, H-1117 Budapest, Hungary
- MTA-ELTE Complex Chemical Systems Research Group, P.O. Box 32, H-1518 Budapest 112, Hungary
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31
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Chemical bonding in the pentagonal-pyramidal benzene dication and analogous isoelectronic hexa-coordinate species. COMPUT THEOR CHEM 2017. [DOI: 10.1016/j.comptc.2017.03.020] [Citation(s) in RCA: 22] [Impact Index Per Article: 3.1] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/17/2022]
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32
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Schwach P, Pan X, Bao X. Direct Conversion of Methane to Value-Added Chemicals over Heterogeneous Catalysts: Challenges and Prospects. Chem Rev 2017; 117:8497-8520. [DOI: 10.1021/acs.chemrev.6b00715] [Citation(s) in RCA: 656] [Impact Index Per Article: 93.7] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/28/2022]
Affiliation(s)
- Pierre Schwach
- State
Key Laboratory of Catalysis, Dalian Institute of Chemical Physics, Chinese Academy of Sciences, Dalian 116023, P.R. China
| | - Xiulian Pan
- State
Key Laboratory of Catalysis, Dalian Institute of Chemical Physics, Chinese Academy of Sciences, Dalian 116023, P.R. China
| | - Xinhe Bao
- State
Key Laboratory of Catalysis, Dalian Institute of Chemical Physics, Chinese Academy of Sciences, Dalian 116023, P.R. China
- Chemistry
Department, Fudan University, Shanghai 200433, P.R. China
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33
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Gupta A, Kumar S, Singh HB. Structural and Reactivity Aspects of Organoselenium and Tellurium Cations. PROCEEDINGS OF THE NATIONAL ACADEMY OF SCIENCES INDIA SECTION A-PHYSICAL SCIENCES 2016. [DOI: 10.1007/s40010-016-0301-1] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.1] [Reference Citation Analysis] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 11/28/2022]
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34
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Schmiedt H, Jensen P, Schlemmer S. Collective Molecular Superrotation: A Model for Extremely Flexible Molecules Applied to Protonated Methane. PHYSICAL REVIEW LETTERS 2016; 117:223002. [PMID: 27925755 DOI: 10.1103/physrevlett.117.223002] [Citation(s) in RCA: 9] [Impact Index Per Article: 1.1] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Received: 06/29/2016] [Indexed: 06/06/2023]
Abstract
The concept of molecular structure is traditionally considered to be virtually fundamental. However, it breaks down in extremely flexible molecules, whose dynamics are governed by large-amplitude motions. For the dynamics of molecules with free internal rotations, we therefore propose a five-dimensional rigid rotor model, with states characterized by two generalized angular momentum quantum numbers and a rotational constant B. The quantum numbers characterize a 5D angular-momentum vector, super-j, which describes collective rotations that involve both the internal and the overall rotation. This model predicts the lowest energy states of the prototypical, extremely flexible molecule, CH_{5}^{+}. Both energies and symmetries compare very favorably to recent experimental results. The respective assignment to the new quantum numbers indicates the validity of our concept of collective rotations in extremely flexible molecules.
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Affiliation(s)
- Hanno Schmiedt
- I. Physikalisches Institut, Universität zu Köln, Zülpicher Strasse 77, D-50937 Köln, Germany
| | - Per Jensen
- Physikalische und Theoretische Chemie, Fakultät für Mathematik und Naturwissenschaften, Bergische Universität Wuppertal, Gauss-Strasse 20, D-42119 Wuppertal, Germany
| | - Stephan Schlemmer
- I. Physikalisches Institut, Universität zu Köln, Zülpicher Strasse 77, D-50937 Köln, Germany
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35
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Mauney DT, Mosley JD, Madison LR, McCoy AB, Duncan MA. Infrared spectroscopy and theory of the formaldehyde cation and its hydroxymethylene isomer. J Chem Phys 2016; 145:174303. [DOI: 10.1063/1.4966214] [Citation(s) in RCA: 8] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/14/2022] Open
Affiliation(s)
- D. T. Mauney
- Department of Chemistry, University of Georgia, Athens, Georgia 30602, USA
| | - J. D. Mosley
- Department of Chemistry, University of Georgia, Athens, Georgia 30602, USA
| | - L. R. Madison
- Department of Chemistry, University of Washington, Seattle, Washington 98195, USA
| | - A. B. McCoy
- Department of Chemistry, University of Washington, Seattle, Washington 98195, USA
| | - M. A. Duncan
- Department of Chemistry, University of Georgia, Athens, Georgia 30602, USA
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36
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Jacovella U, Agner JA, Schmutz H, Deiglmayr J, Merkt F. Infrared spectroscopy of molecular ions in selected rotational and spin-orbit states. J Chem Phys 2016; 145:014301. [DOI: 10.1063/1.4954701] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/14/2022] Open
Affiliation(s)
- U. Jacovella
- Laboratorium für Physikalische Chemie, ETH Zürich, CH-8093 Zurich, Switzerland
| | - J. A. Agner
- Laboratorium für Physikalische Chemie, ETH Zürich, CH-8093 Zurich, Switzerland
| | - H. Schmutz
- Laboratorium für Physikalische Chemie, ETH Zürich, CH-8093 Zurich, Switzerland
| | - J. Deiglmayr
- Laboratorium für Physikalische Chemie, ETH Zürich, CH-8093 Zurich, Switzerland
| | - F. Merkt
- Laboratorium für Physikalische Chemie, ETH Zürich, CH-8093 Zurich, Switzerland
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37
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Wang XG, Carrington T. Calculated rotation-bending energy levels of CH5+ and a comparison with experiment. J Chem Phys 2016; 144:204304. [DOI: 10.1063/1.4948549] [Citation(s) in RCA: 29] [Impact Index Per Article: 3.6] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/15/2022] Open
Affiliation(s)
- Xiao-Gang Wang
- Chemistry Department, Queen’s University, Kingston, Ontario K7L 3N6, Canada
| | - Tucker Carrington
- Chemistry Department, Queen’s University, Kingston, Ontario K7L 3N6, Canada
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38
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Olah GA, Mathew T, Prakash GKS. Relevance and Significance of Extraterrestrial Abiological Hydrocarbon Chemistry. J Am Chem Soc 2016; 138:6905-11. [PMID: 27045758 DOI: 10.1021/jacs.6b03136] [Citation(s) in RCA: 13] [Impact Index Per Article: 1.6] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/19/2022]
Abstract
Astrophysical observations show similarity of observed abiological "organics"-i.e., hydrocarbons, their derivatives, and ions (carbocations and carbanions)-with studied terrestrial chemistry. Their formation pathways, their related extraterrestrial hydrocarbon chemistry originating from carbon and other elements after the Big Bang, their parent hydrocarbon and derivative (methane and methanol, respectively), and transportation of derived building blocks of life by meteorites or comets to planet Earth are discussed in this Perspective. Their subsequent evolution on Earth under favorable "Goldilocks" conditions led to more complex molecules and biological systems, and eventually to humans. The relevance and significance of extraterrestrial hydrocarbon chemistry to the limits of science in relation to the physical aspects of evolution on our planet Earth are also discussed.
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Affiliation(s)
- George A Olah
- Loker Hydrocarbon Research Institute and Department of Chemistry, University of Southern California , Los Angeles, California 90089-1661, United States
| | - Thomas Mathew
- Loker Hydrocarbon Research Institute and Department of Chemistry, University of Southern California , Los Angeles, California 90089-1661, United States
| | - G K Surya Prakash
- Loker Hydrocarbon Research Institute and Department of Chemistry, University of Southern California , Los Angeles, California 90089-1661, United States
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39
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40
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Olah GA, Mathew T, Prakash GKS, Rasul G. Chemical Aspects of Astrophysically Observed Extraterrestrial Methanol, Hydrocarbon Derivatives, and Ions. J Am Chem Soc 2016; 138:1717-22. [DOI: 10.1021/jacs.6b00343] [Citation(s) in RCA: 26] [Impact Index Per Article: 3.3] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/29/2022]
Affiliation(s)
- George A. Olah
- Loker Hydrocarbon Research
Institute and Department of Chemistry, University of Southern California, Los Angeles, California 90089-1661, United States
| | - Thomas Mathew
- Loker Hydrocarbon Research
Institute and Department of Chemistry, University of Southern California, Los Angeles, California 90089-1661, United States
| | - G. K. Surya Prakash
- Loker Hydrocarbon Research
Institute and Department of Chemistry, University of Southern California, Los Angeles, California 90089-1661, United States
| | - Golam Rasul
- Loker Hydrocarbon Research
Institute and Department of Chemistry, University of Southern California, Los Angeles, California 90089-1661, United States
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41
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Wodraszka R, Manthe U. CH+5: Symmetry and the Entangled Rovibrational Quantum States of a Fluxional Molecule. J Phys Chem Lett 2015; 6:4229-4232. [PMID: 26538038 DOI: 10.1021/acs.jpclett.5b01869] [Citation(s) in RCA: 27] [Impact Index Per Article: 3.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 06/05/2023]
Abstract
Protonated methane, CH5+, is the prototypical example of a fluxional molecular system. The almost unconstrained angular motion of its five hydrogen atoms results in dynamical phenomena not found in rigid or semirigid molecules. Here it is shown that standard concepts to describe rotational quantum states of molecules can not be applied to CH5+ or any other fluxional system of the type ABn or Bn with n > 4 due to fundamental symmetry reasons. Instead, the ro-vibrational states of CH5+ display a unique level scheme, which results from a complex entanglement of rotational and tunneling motions. A detailed analysis of the ro-vibrational quantum states of CH5+ based on full-dimensional quantum dynamics simulations is presented, and the effects of the Pauli principle are considered. The consequences for the interpretation of recent experimental results are highlighted
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Affiliation(s)
- Robert Wodraszka
- Theoretische Chemie, Fakultät für Chemie, Universität Bielefeld , Universitätsstraβe 25, D-33615 Bielefeld, Germany
| | - Uwe Manthe
- Theoretische Chemie, Fakultät für Chemie, Universität Bielefeld , Universitätsstraβe 25, D-33615 Bielefeld, Germany
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42
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Mosley JD, Young JW, Huang M, McCoy AB, Duncan MA. Infrared spectroscopy of the methanol cation and its methylene-oxonium isomer. J Chem Phys 2015; 142:114301. [DOI: 10.1063/1.4914146] [Citation(s) in RCA: 22] [Impact Index Per Article: 2.4] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/14/2022] Open
Affiliation(s)
- J. D. Mosley
- Department of Chemistry, University of Georgia, Athens, Georgia 30602, USA
| | - J. W. Young
- Department of Chemistry, University of Georgia, Athens, Georgia 30602, USA
| | - M. Huang
- Department of Chemistry and Biochemistry, The Ohio State University, Columbus, Ohio 43210, USA
| | - A. B. McCoy
- Department of Chemistry and Biochemistry, The Ohio State University, Columbus, Ohio 43210, USA
| | - M. A. Duncan
- Department of Chemistry, University of Georgia, Athens, Georgia 30602, USA
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Affiliation(s)
- Takeshi Oka
- Department of Chemistry and Department of Astronomy and Astrophysics, The Enrico Fermi Institute, University of Chicago, Chicago, IL 60637, USA
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44
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Asvany O, Yamada KMT, Brunken S, Potapov A, Schlemmer S. Experimental ground-state combination differences of CH5+. Science 2015; 347:1346-9. [DOI: 10.1126/science.aaa3304] [Citation(s) in RCA: 93] [Impact Index Per Article: 10.3] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/02/2022]
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45
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Guo Y, Hao Y, Wang H, Xie Y, Schaefer HF. Protonated Digermane, Distannane, and Diplumbane: Can They Be Made in the Laboratory? Eur J Inorg Chem 2014. [DOI: 10.1002/ejic.201402510] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/10/2022]
Affiliation(s)
- Yundong Guo
- School of Engineering and Technology, Neijiang Normal University, Neijiang, Sichuan 641112, P. R. China
| | - Yanjun Hao
- College of Physical Science and Technology, Sichuan University, Chengdu, Sichuan 610064, P. R. China
| | - Hui Wang
- School of Physical Science and Technology, Southwest Jiaotong University, Chengdu 610031, P. R. China
| | - Yaoming Xie
- Center for Computational Quantum Chemistry, University of Georgia, Athens, GA 30602, USA, http://www.ccqc.uga.edu
| | - Henry F. Schaefer
- Center for Computational Quantum Chemistry, University of Georgia, Athens, GA 30602, USA, http://www.ccqc.uga.edu
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Mosley JD, Young JW, Duncan MA. Infrared spectroscopy of the acetyl cation and its protonated ketene isomer. J Chem Phys 2014; 141:024306. [DOI: 10.1063/1.4887074] [Citation(s) in RCA: 10] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/14/2022] Open
Affiliation(s)
- J. D. Mosley
- Department of Chemistry, University of Georgia, Athens, Georgia 30602, USA
| | - J. W. Young
- Department of Chemistry, University of Georgia, Athens, Georgia 30602, USA
| | - M. A. Duncan
- Department of Chemistry, University of Georgia, Athens, Georgia 30602, USA
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The two-component quantum theory of atoms in molecules (TC-QTAIM): the unified theory of localization/delocalization of electrons, nuclei, and exotic elementary particles. Theor Chem Acc 2013. [DOI: 10.1007/s00214-013-1410-4] [Citation(s) in RCA: 13] [Impact Index Per Article: 1.2] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/26/2022]
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48
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Hodges JN, Perry AJ, Jenkins PA, Siller BM, McCall BJ. High-precision and high-accuracy rovibrational spectroscopy of molecular ions. J Chem Phys 2013; 139:164201. [DOI: 10.1063/1.4825251] [Citation(s) in RCA: 26] [Impact Index Per Article: 2.4] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/14/2022] Open
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49
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Petit AS, Ford JE, McCoy AB. Simultaneous Evaluation of Multiple Rotationally Excited States of H3+, H3O+, and CH5+ Using Diffusion Monte Carlo. J Phys Chem A 2013; 118:7206-20. [DOI: 10.1021/jp408821a] [Citation(s) in RCA: 13] [Impact Index Per Article: 1.2] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/28/2022]
Affiliation(s)
- Andrew S. Petit
- Department of Chemistry and Biochemistry, The Ohio State University, Columbus, Ohio 43210, United States
| | - Jason E. Ford
- Department of Chemistry and Biochemistry, The Ohio State University, Columbus, Ohio 43210, United States
| | - Anne B. McCoy
- Department of Chemistry and Biochemistry, The Ohio State University, Columbus, Ohio 43210, United States
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50
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Thomas RD, Kashperka I, Vigren E, Geppert WD, Hamberg M, Larsson M, af Ugglas M, Zhaunerchyk V. Dissociative recombination of CH4(+). J Phys Chem A 2013; 117:9999-10005. [PMID: 23651407 DOI: 10.1021/jp400353x] [Citation(s) in RCA: 8] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/30/2022]
Abstract
CH4(+) is an important molecular ion in the astrochemistry of diffuse clouds, dense clouds, cometary comae, and planetary ionospheres. However, the rate of one of the common destruction mechanisms for molecular ions in these regions, dissociative recombination (DR), is somewhat uncertain. Here, we present absolute measurements for the DR of CH4(+) made using the heavy ion storage ring CRYRING in Stockholm, Sweden. From our collision-energy dependent cross-sections, we infer a thermal rate constant of k(Te) = 1.71(±0.02) × 10(–6)(Te/300)(−0.66(±0.02)) cm3 s(–1) over the region of electron temperatures 10 ≤ Te ≤ 1000 K. At low collision energies, we have measured the branching fractions of the DR products to be CH4 (0.00 ± 0.00); CH3 + H (0.18 ± 0.03); CH2 + 2H (0.51 ± 0.03); CH2 + H2 (0.06 ± 0.01); CH + H2 + H (0.23 ± 0.01); and CH + 2H2 (0.02 ± 0.01), indicating that two or more C–H bonds are broken in 80% of all collisions.
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Affiliation(s)
- Richard D Thomas
- Department of Physics, Stockholm University , Albanova University Center, SE-106 91 Stockholm, Sweden
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