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Rapacioli M, Buey MY, Spiegelman F. Addressing electronic and dynamical evolution of molecules and molecular clusters: DFTB simulations of energy relaxation in polycyclic aromatic hydrocarbons. Phys Chem Chem Phys 2024; 26:1499-1515. [PMID: 37933901 PMCID: PMC10793726 DOI: 10.1039/d3cp02852f] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/19/2023] [Accepted: 10/17/2023] [Indexed: 11/08/2023]
Abstract
We present a review of the capabilities of the density functional based Tight Binding (DFTB) scheme to address the electronic relaxation and dynamical evolution of molecules and molecular clusters following energy deposition via either collision or photoabsorption. The basics and extensions of DFTB for addressing these systems and in particular their electronic states and their dynamical evolution are reviewed. Applications to PAH molecules and clusters, carbonaceous systems of major interest in astrochemical/astrophysical context, are reported. A variety of processes are examined and discussed such as collisional hydrogenation, fast collisional processes and induced electronic and charge dynamics, collision-induced fragmentation, photo-induced fragmentation, relaxation in high electronic states, electronic-to-vibrational energy conversion and statistical versus non-statistical fragmentation. This review illustrates how simulations may help to unravel different relaxation mechanisms depending on various factors such as the system size, specific electronic structure or excitation conditions, in close connection with experiments.
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Affiliation(s)
- Mathias Rapacioli
- Laboratoire de Chimie et Physique Quantique (LCPQ/FERMI), UMR5626, Université de Toulouse (UPS) and CNRS, 118 Route de Narbonne, F-31062 Toulouse, France.
| | - Maysa Yusef Buey
- Laboratoire de Chimie et Physique Quantique (LCPQ/FERMI), UMR5626, Université de Toulouse (UPS) and CNRS, 118 Route de Narbonne, F-31062 Toulouse, France.
| | - Fernand Spiegelman
- Laboratoire de Chimie et Physique Quantique (LCPQ/FERMI), UMR5626, Université de Toulouse (UPS) and CNRS, 118 Route de Narbonne, F-31062 Toulouse, France.
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2
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Oliveira RR, Molpeceres G, Montserrat R, Fantuzzi F, Rocha AB, Kästner J. Gas-phase C 60H n+q ( n = 0-4, q = 0,1) fullerenes and fulleranes: spectroscopic simulations shed light on cosmic molecular structures. Phys Chem Chem Phys 2023; 25:25746-25760. [PMID: 37724022 DOI: 10.1039/d3cp03254j] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 09/20/2023]
Abstract
The discovery of C60, C60+, and C70 in the interstellar medium has ignited a profound interest in the astrochemistry of fullerene and related systems. In particular, the presence of diffuse interstellar bands and their association with C60+ has led to the hypothesis that hydrogenated derivatives, known as fulleranes, may also exist in the interstellar medium and contribute to these bands. In this study, we systematically investigated the structural and spectroscopic properties of C60Hn+q (n = 0-4, q = 0,1) using an automated global minimum search and density functional theory calculations. Our results revealed novel global minimum structures for C60H2 and C60H4, distinct from previous reports. Notably, all hydrogenated fullerenes exhibited lower ionization potentials and higher proton affinities compared to C60. From an astrochemical perspective, our results exposed the challenges in establishing definitive spectroscopic criteria for detecting fulleranes using mid-infrared and UV-Vis spectroscopies. However, we successfully identified distinct electronic transitions in the near-infrared range that serve as distinctive signatures of cationic fulleranes. We strongly advocate for further high-resolution experimental studies to fully explore the potential of these transitions for the interstellar detection of fulleranes.
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Affiliation(s)
- Ricardo R Oliveira
- Chemistry Institute, Federal University of Rio de Janeiro, Rio de Janeiro, Brazil.
| | - Germán Molpeceres
- Department of Astronomy, Graduate School of Science, The University of Tokyo, Tokyo 113 0033, Japan
| | - Ricardo Montserrat
- Chemistry Institute, Federal University of Rio de Janeiro, Rio de Janeiro, Brazil.
| | - Felipe Fantuzzi
- School of Chemistry and Forensic Science, University of Kent, Canterbury CT2 7NH, UK
| | - Alexandre B Rocha
- Chemistry Institute, Federal University of Rio de Janeiro, Rio de Janeiro, Brazil.
| | - Johannes Kästner
- Institute for Theoretical Chemistry, University of Stuttgart, Stuttgart, Germany
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3
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Peeters E, Mackie C, Candian A, Tielens AGGM. A Spectroscopic View on Cosmic PAH Emission. Acc Chem Res 2021; 54:1921-1933. [PMID: 33780617 DOI: 10.1021/acs.accounts.0c00747] [Citation(s) in RCA: 22] [Impact Index Per Article: 7.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/30/2022]
Abstract
ConspectusPolycyclic aromatic hydrocarbon molecules (PAHs) are ubiquitously present at high abundances in the Universe. They are detected through their infrared (IR) fluorescence UV pumped by nearby massive stars. Hence, their infrared emission is used to determine the star formation rate in galaxies, one of the key indicators for understanding the evolution of galaxies. Together with fullerenes, PAHs are the largest molecules found in space. They significantly partake in a variety of physical and chemical processes in space, influencing star and planet formation as well as galaxy evolution.Since the IR features from PAHs originate from chemical bonds involving only nearest neighbor atoms, they have only a weak dependence on the size and structure of the molecule, and it is therefore not possible to identify the individual PAH molecules that make up the cosmic PAH family. This strongly hampers the interpretation of their astronomical fingerprints. Despite the lack of identification, constraints can be set on the characteristics of the cosmic PAH family thanks to a joint effort of astronomers, physicists, and chemists.This Account presents the spectroscopic properties of the cosmic PAH emission as well as the intrinsic spectroscopic properties of PAHs and astronomical modeling of the PAH evolution required for the interpretation of the cosmic PAH characteristics. We discuss the observed spectral signatures tracing PAH properties such as charge, size, and structure and highlight the related challenges. We discuss the recent success of anharmonic calculations of PAH infrared absorption and emission spectra and outline the path forward. Finally, we illustrate the importance of models on PAH processing for the interpretation of the astronomical data in terms of the charge balance and PAH destruction.Throughout this Account, we emphasize that huge progress is on the horizon on the astronomical front. Indeed, the world is eagerly awaiting the launch of the James Webb Space Telescope (JWST). With its incredible improvement in spatial resolution, combined with its complete spectral coverage of the PAH infrared emission bands at medium spectral resolution and superb sensitivity, the JWST will revolutionize PAH research. Previous observations could only present spectra averaged over regions with vastly different properties, thus greatly confusing their interpretation. The amazing spatial resolution of JWST will disentangle these different regions. This will allow us to quantify precisely how PAHs are modified by the physical conditions of their host environment and thus trace how PAHs evolve across space. However, this will only be achieved when the necessary (and still missing) fundamental properties of PAHs, outlined in this Account, are known. We strongly encourage you to join this effort.
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Affiliation(s)
- Els Peeters
- Department of Physics & Astronomy, University of Western Ontario, London, Ontario, Canada
- Institute for Earth and Space Exploration, University of Western Ontario, London, Ontario, Canada
- SETI Institute, 189 Bernardo Avenue, Suite 100, Mountain View, California 94043, United States
| | - Cameron Mackie
- Lawrence Berkeley National Laboratory, University of California, Berkeley, California 94720, United States
| | - Alessandra Candian
- van’t Hoff Institute for Molecular Sciences, University of Amsterdam, Amsterdam, The Netherlands
- Leiden Observatory, Leiden University, Leiden, The Netherlands
| | - Alexander G. G. M. Tielens
- Leiden Observatory, Leiden University, Leiden, The Netherlands
- University of Maryland, College Park, Maryland 20742, United States
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4
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Campisi D, Lamberts T, Dzade NY, Martinazzo R, ten Kate IL, Tielens AGGM. Interaction of Aromatic Molecules with Forsterite: Accuracy of the Periodic DFT-D4 Method. J Phys Chem A 2021; 125:2770-2781. [PMID: 33784098 PMCID: PMC8154625 DOI: 10.1021/acs.jpca.1c02326] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/15/2021] [Indexed: 12/02/2022]
Abstract
Density functional theory (DFT) has provided deep atomic-level insights into the adsorption behavior of aromatic molecules on solid surfaces. However, modeling the surface phenomena of large molecules on mineral surfaces with accurate plane wave methods (PW) can be orders of magnitude more computationally expensive than localized atomic orbitals (LCAO) methods. In the present work, we propose a less costly approach based on the DFT-D4 method (PBE-D4), using LCAO, to study the interactions of aromatic molecules with the {010} forsterite (Mg2SiO4) surface for their relevance in astrochemistry. We studied the interaction of benzene with the pristine {010} forsterite surface and with transition-metal cations (Fe2+ and Ni2+) using PBE-D4 and a vdW-inclusive density functional (Dion, Rydberg, Schröder, Langreth, and Lundqvist (DRSLL)) with LCAO methods. PBE-D4 shows good agreement with coupled-cluster methods (CCSD(T)) for the binding energy trend of cation complexes and with PW methods for the binding energy of benzene on the forsterite surface with a difference of about 0.03 eV. The basis set superposition error (BSSE) correction is shown to be essential to ensure a correct estimation of the binding energies even when large basis sets are employed for single-point calculations of the optimized structures with smaller basis sets. We also studied the interaction of naphthalene and benzocoronene on pristine and transition-metal-doped {010} forsterite surfaces as a test case for PBE-D4. Yielding results that are in good agreement with the plane wave methods with a difference of about 0.02-0.17 eV, the PBE-D4 method is demonstrated to be effective in unraveling the binding structures and the energetic trends of aromatic molecules on pristine and transition-metal-doped forsterite mineral surfaces. Furthermore, PBE-D4 results are in good agreement with its predecessor PBE-D3(BJM) and with the vdW-inclusive density functionals, as long as transition metals are not involved. Hence, PBE-D4/CP-DZP has been proven to be a robust theory level to study the interaction of aromatic molecules on mineral surfaces.
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Affiliation(s)
- Dario Campisi
- Leiden
Observatory, Leiden University, Niels Bohrweg 2, 2333 CA Leiden, The Netherlands
| | - Thanja Lamberts
- Leiden
Observatory, Leiden University, Niels Bohrweg 2, 2333 CA Leiden, The Netherlands
- Leiden
Institute of Chemistry, Leiden University, Einsteinweg 55, 2300
RA Leiden, The Netherlands
| | - Nelson Y. Dzade
- Cardiff
University, Main Building, Park Place, CF10 3AT Cardiff, U.K.
| | - Rocco Martinazzo
- Department
of Chemistry, Universitá degli Studi
di Milano, Via Golgi 19, 20133 Milan, Italy
| | - Inge Loes ten Kate
- Department
of Earth Sciences, Faculty of Geosciences, Utrecht University, Princetonlaan 8a, 3584 CB Utrecht, The Netherlands
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Campisi D, Simonsen FDS, Thrower JD, Jaganathan R, Hornekær L, Martinazzo R, Tielens AGGM. Superhydrogenation of pentacene: the reactivity of zigzag-edges. Phys Chem Chem Phys 2020; 22:1557-1565. [PMID: 31872819 DOI: 10.1039/c9cp05440e] [Citation(s) in RCA: 16] [Impact Index Per Article: 4.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/21/2022]
Abstract
Investigating the hydrogenation of carbonaceous materials is of interest in a wide range of research areas including electronic device development, hydrogen storage, and, in particular, astrocatalytic formation of molecular hydrogen in the universe. Polycyclic Aromatic Hydrocarbons (PAHs) are ubiquitous in space, locking up close to 15% of the elementary carbon. We have used thermal desorption measurements to study the hydrogenation sequence of pentacene from adding one additional H to the fully hydrogenated pentacene species. The experiments reveal that hydrogenated species with an even number of excess H atoms are highly preferred over hydrogenated species with an odd number of H atoms. In addition, the experiments show that specific hydrogenation states of pentacene with 2, 4, 6, 10, 16 and 22 extra H atoms are preferred over other even numbers. We have investigated the structural stability and activation energy barriers for the superhydrogenation of pentacene using Density Functional Theory. The results reveal a preferential hydrogenation pattern set by the activation energy barriers of the hydrogenation steps. Based on these studies, we formulate simple concepts governing the hydrogenation that apply equally well for different PAHs.
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Affiliation(s)
- Dario Campisi
- Leiden Observatory, Leiden University, Niels Bohrweg 2, 2333 CA Leiden, The Netherlands.
| | | | - John D Thrower
- Department of Physics and Astronomy, Aarhus University, Ny Munkegade 120, DK-8000 Aarhus C, Denmark
| | - Rijutha Jaganathan
- Department of Physics and Astronomy, Aarhus University, Ny Munkegade 120, DK-8000 Aarhus C, Denmark
| | - Liv Hornekær
- Department of Physics and Astronomy, Aarhus University, Ny Munkegade 120, DK-8000 Aarhus C, Denmark and Interdisciplinary Nano-Science Centre (iNano), Aarhus University, Denmark
| | - Rocco Martinazzo
- Department of Chemistry, Università degli Studi di Milano, Via Golgi 19, 20133, Milan, Italy
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6
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Sánchez M, Ruette F. Calculations of adsorption, coadsorption, diffusion, and reaction barriers of H atoms in the H2 formation on a positively charged coronene. Chem Phys Lett 2020. [DOI: 10.1016/j.cplett.2019.136913] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/28/2022]
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7
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Diedhiou M, West BJ, Bouwman J, Mayer PM. Ion Dissociation Dynamics of 1,2,3,4-Tetrahydronaphthalene: Tetralin as a Test Case For Hydrogenated Polycyclic Aromatic Hydrocarbons. J Phys Chem A 2019; 123:10885-10892. [PMID: 31794665 DOI: 10.1021/acs.jpca.9b09511] [Citation(s) in RCA: 7] [Impact Index Per Article: 1.4] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/30/2022]
Abstract
The unimolecular dissociation of ionized tetralin was probed by tandem mass spectrometry, imaging photoelectron photoion coincidence (iPEPICO) spectroscopy, and theory. The major reactions observed were the loss of the hydrocarbons CH3•, C2H4, and C3H5• together with H•-atom loss. RRKM modeling of the iPEPICO data suggested a two-well potential energy surface. Ionized tetralin can lose all four neutrals via H-shift and ring-opening reactions or CH3• and C2H4 after interconversion to the 1-methylindane ion, a process similar to that found for ionized 1,2-dihydronaphthalene (isomerizing to form the 1-methylindene ion structure). This was confirmed at the B3LYP/6-31+G(d,p) level of theory, and potential mechanisms for all reactions are described. The ionization energy of tetralin was established from the threshold photoelectron spectrum to be 8.46 ± 0.01 eV.
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Affiliation(s)
- Malick Diedhiou
- Department of Chemistry and Biomolecular Sciences , University of Ottawa , Ottawa , Canada K1N 6N5
| | - Brandi J West
- Department of Chemistry and Biomolecular Sciences , University of Ottawa , Ottawa , Canada K1N 6N5
| | - Jordy Bouwman
- Laboratory for Astrophysics, Leiden Observatory , Leiden University , P.O. Box 9513, 2300RA Leiden , The Netherlands
| | - Paul M Mayer
- Department of Chemistry and Biomolecular Sciences , University of Ottawa , Ottawa , Canada K1N 6N5
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8
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Thrower JD, Pantazidis G, Scheffler M, Simonsen FDS, Jensen PA, Hornekær L. Laboratory evidence for the formation of hydrogenated fullerene molecules. PROCEEDINGS OF THE INTERNATIONAL ASTRONOMICAL UNION. INTERNATIONAL ASTRONOMICAL UNION 2019; 15:144-147. [PMID: 33072168 PMCID: PMC7116202 DOI: 10.1017/s1743921319007567] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.2] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 11/06/2022]
Abstract
Experimental evidence for the formation of hydrogenated fullerene molecules is presented. Films of C60 were grown on a highly oriented pyrolytic graphite (substrate) and exposed to a beam of deuterium atoms. Thermal desorption combined with mass spectrometry was used to determine the deuterated fullerene products formed, revealing a maximum degree of deuteration corresponding to C60D36. Release of D2 from the deuterated C60 film occurs at a much higher temperature than for D-saturated graphite.
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Affiliation(s)
- J. D. Thrower
- Department of Physics & Astronomy, Aarhus University, 8000 Aarhus C, Denmark
| | - G. Pantazidis
- Department of Physics & Astronomy, Aarhus University, 8000 Aarhus C, Denmark
| | - M. Scheffler
- Department of Physics & Astronomy, Aarhus University, 8000 Aarhus C, Denmark
| | - F. D. S Simonsen
- Department of Physics & Astronomy, Aarhus University, 8000 Aarhus C, Denmark
| | - P. A. Jensen
- Department of Physics & Astronomy, Aarhus University, 8000 Aarhus C, Denmark
| | - L. Hornekær
- Department of Physics & Astronomy, Aarhus University, 8000 Aarhus C, Denmark
- Interdisciplinary Nanoscience Center (iNANO), Aarhus University, 8000 Aarhus C, Denmark
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9
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Abstract
Coronene is known in chemistry as an aromatic or even superaromatic molecule while it has 24 π-electrons which does not conform to the 4 n + 2 Huckel's rule. Chemical bonding description of it is not settled in chemistry and five models were reported in the literature. According to our model, coronene has two concentric π-systems responsible for aromaticity inside of the molecule. In addition to that there are six peripheral 2c-2e π-bonds, which makes coronene aliphatic/aromatic at the same time. However, recent experiments and calculations put in question the presence of peripheral π-bonds. In order to resolve this issue, we computationally studied reaction mechanism of the Cl2 molecule with C2H4, C6H6, and C24H12. As it turned out, coronene behaves in a way similar to ethylene by adding Cl2 molecule. Thus, it proves that coronene indeed has peripheral double bonds which is also consistent with its experimental geometrical features. Our chemical bonding model allows to identify the most reactive atoms in coronene and other PAHs; therefore, it is a matter of importance for combustion and soot formation studies.
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Affiliation(s)
- Nikita Fedik
- Department of Chemistry and Biochemistry , Utah State University , Logan , Utah 84322 , United States
| | - Alexander I Boldyrev
- Department of Chemistry and Biochemistry , Utah State University , Logan , Utah 84322 , United States
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10
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Rapacioli M, Cazaux S, Foley N, Simon A, Hoekstra R, Schlathölter T. Atomic hydrogen interactions with gas-phase coronene cations: hydrogenation versus fragmentation. Phys Chem Chem Phys 2018; 20:22427-22438. [PMID: 29947389 DOI: 10.1039/c8cp03024c] [Citation(s) in RCA: 19] [Impact Index Per Article: 3.2] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/18/2022]
Abstract
Sequential hydrogenation of polycyclic aromatic hydrocarbon (PAH) cations drives a gradual transition from a planar to a puckered geometry and from an aromatic to an aliphatic electronic structure. The resulting H-induced weakening of the molecular structure together with the exothermic nature of the consecutive H-attachment processes can lead to substantial molecular fragmentation. We have studied H attachment to gas-phase coronene cations in a radiofrequency ion trap using tandem mass spectrometry. With increasing hydrogenation, C2Hi loss and multifragmentation are identified as main de-excitation channels. To understand the dependence of both channels on H-exposure time, we have simulated the molecular stability and fragmentation channels of hydrogenated PAHs using a molecular dynamics approach employing potential energies determined by a density functional based tight binding method. As the coronene fragmentation patterns depend on the balance between energy deposition by H-attachment and the extent of cooling in between subsequent attachment processes, we investigate several scenarios for the energy distribution of hydrogenated PAHs. Good agreement between experiment and simulation is reached, when realistic energy distributions are considered.
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Affiliation(s)
- Mathias Rapacioli
- Laboratoire de Chimie et Physique Quantiques LCPQ/IRSAMC, UMR5626, Université de Toulouse (UPS) and CNRS, 118 Route de Narbonne, F-31062 Toulouse, France
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11
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Domaracka A, Delaunay R, Mika A, Gatchell M, Zettergren H, Cederquist H, Rousseau P, Huber BA. Ion collision-induced chemistry in pure and mixed loosely bound clusters of coronene and C 60 molecules. Phys Chem Chem Phys 2018; 20:15052-15060. [PMID: 29790511 DOI: 10.1039/c8cp01179f] [Citation(s) in RCA: 7] [Impact Index Per Article: 1.2] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/30/2023]
Abstract
Ionization, fragmentation and molecular growth have been studied in collisions of 22.5 keV He2+- or 3 keV Ar+-projectiles with pure loosely bound clusters of coronene (C24H12) molecules or with loosely bound mixed C60-C24H12 clusters by using mass spectrometry. The heavier and slower Ar+ projectiles induce prompt knockout-fragmentation - C- and/or H-losses - from individual molecules and highly efficient secondary molecular growth reactions before the clusters disintegrate on picosecond timescales. The lighter and faster He2+ projectiles have a higher charge and the main reactions are then ionization by ions that are not penetrating the clusters. This leads mostly to cluster fragmentation without molecular growth. However, here penetrating collisions may also lead to molecular growth but to a much smaller extent than with 3 keV Ar+. Here we present fragmentation and molecular growth mass distributions with 1 mass unit resolution, which reveals that the same numbers of C- and H-atoms often participate in the formation and breaking of covalent bonds inside the clusters. We find that masses close to those with integer numbers of intact coronene molecules, or with integer numbers of both intact coronene and C60 molecules, are formed where often one or several H-atoms are missing or have been added on. We also find that super-hydrogenated coronene is formed inside the clusters.
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Affiliation(s)
- Alicja Domaracka
- Normandie Univ, ENSICAEN, UNICAEN, CEA, CNRS, CIMAP, 14000 Caen, France.
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12
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Hydrogenated Benzene in Circumstellar Environments: Insights into the Photostability of Super-hydrogenated PAHs. ACTA ACUST UNITED AC 2018. [DOI: 10.3847/1538-4357/aaa977] [Citation(s) in RCA: 14] [Impact Index Per Article: 2.3] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/18/2022]
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13
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Goulart M, Kuhn M, Rasul B, Postler J, Gatchell M, Zettergren H, Scheier P, Echt O. The structure of coronene cluster ions inferred from H 2 uptake in the gas phase. Phys Chem Chem Phys 2018; 19:27968-27973. [PMID: 29022968 DOI: 10.1039/c7cp04999d] [Citation(s) in RCA: 12] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/21/2022]
Abstract
Mass spectra of helium nanodroplets doped with H2 and coronene feature anomalies in the ion abundance that reveal anomalies in the energetics of adsorption sites. The coronene monomer ion strongly adsorbs up to n = 38 H2 molecules indicating a commensurate solvation shell that preserves the D6h symmetry of the substrate. No such feature is seen in the abundance of the coronene dimer through tetramer complexed with H2; this observation rules out a vertical columnar structure. Instead we see evidence for a columnar structure in which adjacent coronenes are displaced in parallel, forming terraces that offer additional strong adsorption sites. The experimental value for the number of adsorption sites per terrace, approximately six, barely depends on the number of coronene molecules. The displacement estimated from this number exceeds the value reported in several theoretical studies of the bare, neutral coronene dimer.
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Affiliation(s)
- Marcelo Goulart
- Institut für Ionenphysik und Angewandte Physik, Universität Innsbruck, Technikerstr. 25, A-6020 Innsbruck, Austria.
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14
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Wakelam V, Bron E, Cazaux S, Dulieu F, Gry C, Guillard P, Habart E, Hornekær L, Morisset S, Nyman G, Pirronello V, Price SD, Valdivia V, Vidali G, Watanabe N. H 2 formation on interstellar dust grains: The viewpoints of theory, experiments, models and observations. ACTA ACUST UNITED AC 2017. [DOI: 10.1016/j.molap.2017.11.001] [Citation(s) in RCA: 90] [Impact Index Per Article: 12.9] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/18/2022]
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15
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Morisset S, Rougeau N, Teillet-Billy D. Influence of a graphene surface on the first steps of the hydrogenation of a coronene molecule. Chem Phys Lett 2017. [DOI: 10.1016/j.cplett.2017.05.004] [Citation(s) in RCA: 4] [Impact Index Per Article: 0.6] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/19/2022]
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16
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Karton A. How reliable is DFT in predicting relative energies of polycyclic aromatic hydrocarbon isomers? comparison of functionals from different rungs of jacob's ladder. J Comput Chem 2016; 38:370-382. [DOI: 10.1002/jcc.24669] [Citation(s) in RCA: 26] [Impact Index Per Article: 3.3] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/19/2016] [Revised: 10/21/2016] [Accepted: 10/27/2016] [Indexed: 12/14/2022]
Affiliation(s)
- Amir Karton
- School of Chemistry and BiochemistryThe University of Western AustraliaPerthWestern Australia 6009 Australia
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PHOTO-STABILITY OF SUPER-HYDROGENATED PAHs DETERMINED BY ACTION SPECTROSCOPY EXPERIMENTS. ACTA ACUST UNITED AC 2016. [DOI: 10.3847/0004-637x/832/1/24] [Citation(s) in RCA: 24] [Impact Index Per Article: 3.0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/01/2023]
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