1
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Ferrari P, Kaw KA, Lievens P, Janssens E. Radiative cooling in silver and palladium doped gold clusters. Faraday Discuss 2023; 242:269-285. [PMID: 36168998 DOI: 10.1039/d2fd00090c] [Citation(s) in RCA: 1] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 02/03/2023]
Abstract
The emission of photons from a thermally populated electronic excited state, via the process of recurrent fluorescence, has been recognized as a prominent cooling channel in hot molecules and small metal clusters. For the latter case, however, only monometallic species have been investigated to date. An active radiative cooling channel has a stabilizing effect and can favor the size and composition specific production of selected clusters. In this work, the influence of silver and palladium doping on the radiative cooling of gold cluster cations is studied. The quenching of metastable fragmentation due to radiation of laser-excited Aun+, AgAun-1+ and PdAun-1+ (n = 11-15) clusters is investigated in a single-pass molecular beam setup. The observed high radiation rates, with values in the range from 103 to 105 s-1, are consistent with recurrent fluorescence. The rates present a pronounced odd-even staggering with higher values for the clusters with closed-shell electronic configurations. While substitution of Au with Ag does not alter the odd-even pattern with cluster size, replacing Au with Pd shifts the pattern by one atom. The experimental observations are discussed in terms of the dissociation energy of the clusters, which sets their effective temperature during photon emission, and the low-lying electronic excited states involved in the photon emission process. Linear-response time-dependent density functional theory calculations on selected species are used to illustrate the significant effect of the electronic structure on the radiation rates. For n = 14, substitution of Au with Ag lowers the energy of the lowest-energy transition in the cluster, which in addition has a higher oscillator strength, favoring radiative cooling. The opposite effect is seen in Pd doped clusters. Based on this analysis, conclusions can be drawn about the significance of radiative cooling in laser-excited alloy clusters, with a concomitant fast stabilization at high internal energy conditions.
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Affiliation(s)
- Piero Ferrari
- Quantum Solid-State Physics, Department of Physics and Astronomy, KU Leuven, Celestijnenlaan 200d, Leuven 3001, Belgium.
| | - Kevin Anthony Kaw
- Quantum Solid-State Physics, Department of Physics and Astronomy, KU Leuven, Celestijnenlaan 200d, Leuven 3001, Belgium.
| | - Peter Lievens
- Quantum Solid-State Physics, Department of Physics and Astronomy, KU Leuven, Celestijnenlaan 200d, Leuven 3001, Belgium.
| | - Ewald Janssens
- Quantum Solid-State Physics, Department of Physics and Astronomy, KU Leuven, Celestijnenlaan 200d, Leuven 3001, Belgium.
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2
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Stockett MH, Bull JN, Cederquist H, Indrajith S, Ji M, Navarro Navarrete JE, Schmidt HT, Zettergren H, Zhu B. Efficient stabilization of cyanonaphthalene by fast radiative cooling and implications for the resilience of small PAHs in interstellar clouds. Nat Commun 2023; 14:395. [PMID: 36693859 PMCID: PMC9873784 DOI: 10.1038/s41467-023-36092-0] [Citation(s) in RCA: 5] [Impact Index Per Article: 5.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/19/2022] [Accepted: 01/13/2023] [Indexed: 01/25/2023] Open
Abstract
After decades of searching, astronomers have recently identified specific Polycyclic Aromatic Hydrocarbons (PAHs) in space. Remarkably, the observed abundance of cyanonaphthalene (CNN, C10H7CN) in the Taurus Molecular Cloud (TMC-1) is six orders of magnitude higher than expected from astrophysical modeling. Here, we report unimolecular dissociation and radiative cooling rate coefficients of the 1-CNN isomer in its cationic form. These results are based on measurements of the time-dependent neutral product emission rate and kinetic energy release distributions produced from an ensemble of internally excited 1-CNN+ studied in an environment similar to that in interstellar clouds. We find that Recurrent Fluorescence - radiative relaxation via thermally populated electronic excited states - efficiently stabilizes 1-CNN+, owing to a large enhancement of the electronic transition probability by vibronic coupling. Our results help explain the anomalous abundance of CNN in TMC-1 and challenge the widely accepted picture of rapid destruction of small PAHs in space.
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Affiliation(s)
- Mark H. Stockett
- grid.10548.380000 0004 1936 9377Department of Physics, Stockholm University, Stockholm, Sweden
| | - James N. Bull
- grid.8273.e0000 0001 1092 7967School of Chemistry, University of East Anglia, Norwich, United Kingdom
| | - Henrik Cederquist
- grid.10548.380000 0004 1936 9377Department of Physics, Stockholm University, Stockholm, Sweden
| | - Suvasthika Indrajith
- grid.10548.380000 0004 1936 9377Department of Physics, Stockholm University, Stockholm, Sweden
| | - MingChao Ji
- grid.10548.380000 0004 1936 9377Department of Physics, Stockholm University, Stockholm, Sweden
| | | | - Henning T. Schmidt
- grid.10548.380000 0004 1936 9377Department of Physics, Stockholm University, Stockholm, Sweden
| | - Henning Zettergren
- grid.10548.380000 0004 1936 9377Department of Physics, Stockholm University, Stockholm, Sweden
| | - Boxing Zhu
- grid.10548.380000 0004 1936 9377Department of Physics, Stockholm University, Stockholm, Sweden
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3
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Concina B, Bordas C. Thermionic Emission of Negative Ions of Molecules and Small Clusters as a Probe of Low-Energy Attachment. J Phys Chem A 2022; 126:7442-7451. [PMID: 36221803 DOI: 10.1021/acs.jpca.2c04530] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/29/2022]
Abstract
We have been studying the thermionic emission of negatively charged molecules and small clusters for more than a decade. The kinetic energy released distribution (KERD) of mass-selected negative ions has been measured with a velocity map imaging spectrometer. A comparison of the experimental KERD to detailed balance models provided information on the reverse process, namely, the electron attachment to the parent. The electron attachment to neutral systems (reverse process of the electron emission from anions) is usually described in a simplified way as a single electron capture in the framework of the classical Langevin model. Our measurements show that this approach is insufficient and that, in addition to the capture step, an intramolecular vibrational redistribution (IVR) step should be included. As far as multiply charged anions are concerned, the electron attachment to anions (reverse process of the electron emission from dianions) is strongly affected by the repulsive Coulomb barrier (RCB). Previous studies assumed a pure over-the-barrier process, which is in disagreement with our study. Indeed, electron emission is measured below the RCB, revealing significant thermal tunneling. In the present review, we summarize these works on singly and doubly charged anions in an attempt to present a unified view of the involved processes. It is worth noting that the detailed measurements of KERDs in the very low kinetic energy region (typically around 0.1 eV) have been made possible thanks to electron imaging methods, without which all of this work could never have been done, with time-resolution capabilities allowing the disentangling of direct and delayed electron emission.
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Affiliation(s)
- Bruno Concina
- Université de Lyon, Université Claude Bernard Lyon 1, CNRS, Institut Lumière Matière, F-69622Villeurbanne, France
| | - Christian Bordas
- Université de Lyon, Université Claude Bernard Lyon 1, CNRS, Institut Lumière Matière, F-69622Villeurbanne, France
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4
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Gnaser H, Martschini M, Leimbach D, Karls J, Hanstorp D, Indrajith S, Ji M, Martini P, Simonsson A, Zettergren H, Schmidt HT, Golser R. Spontaneous and photo-induced decay processes of WF 5 - and HfF 5 - molecular anions in a cryogenic storage ring. J Chem Phys 2022; 157:044304. [PMID: 35922356 DOI: 10.1063/5.0097896] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/15/2022] Open
Abstract
Spontaneous and photo-induced decay processes of HfF5 - and WF5 - molecular anions were investigated in the Double ElectroStatic Ion Ring ExpEriment (DESIREE). The observation of these reactions over long time scales (several tens of ms) was possible due to the cryogenic temperatures (13 K) and the extremely low residual gas pressure (∼10-14 mbar) of DESIREE. For photo-induced reactions, laser wavelengths in the range 240 to 450 nm were employed. Both anion species were found to undergo spontaneous decay via electron detachment or fragmentation. After some ms, radiative cooling processes were observed to lower the probability for further decay through these processes. Photo-induced reactions indicate the existence of an energy threshold for WF5 - anions at about 3.5 eV, above which the neutralization yield increases strongly. By contrast, HfF5 - ions exhibit essentially no enhanced production of neutrals upon photon interaction, even for the highest photon energy used in this experiment (∼5.2 eV). This suppression will be highly beneficial for the efficient detection, in accelerator mass spectrometry, of the extremely rare isotope 182Hf using the 182HfF5 - anion while effectively reducing the interfering stable isobar 182W in the analyte ion 182WF5 -. The radionuclide 182Hf is of great relevance in astrophysical environments as it constitutes a potential candidate to study the events of nucleosynthesis that may have taken place in the vicinity of the solar system several million years ago.
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Affiliation(s)
- Hubert Gnaser
- University of Vienna, Faculty of Physics, Isotope Physics - VERA Laboratory, A-1090 Wien, Austria
| | - Martin Martschini
- University of Vienna, Faculty of Physics, Isotope Physics - VERA Laboratory, A-1090 Wien, Austria
| | - David Leimbach
- Department of Physics, University of Gothenburg, SE-41296 Gothenburg, Sweden
| | - Julia Karls
- Department of Physics, University of Gothenburg, SE-41296 Gothenburg, Sweden
| | - Dag Hanstorp
- Department of Physics, University of Gothenburg, SE-41296 Gothenburg, Sweden
| | | | - Mingchao Ji
- Department of Physics, Stockholm University, SE-10691 Stockholm, Sweden
| | - Paul Martini
- Department of Physics, Stockholm University, SE-10691 Stockholm, Sweden
| | - Ansgar Simonsson
- Department of Physics, Stockholm University, SE-10691 Stockholm, Sweden
| | | | - Henning T Schmidt
- Department of Physics, Stockholm University, SE-10691 Stockholm, Sweden
| | - Robin Golser
- University of Vienna, Faculty of Physics, Isotope Physics - VERA Laboratory, A-1090 Wien, Austria
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5
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Lacinbala O, Calvo F, Dubosq C, Falvo C, Parneix P, Rapacioli M, Simon A, Pino T. Radiative relaxation in isolated large carbon clusters: Vibrational emission versus recurrent fluorescence. J Chem Phys 2022; 156:144305. [DOI: 10.1063/5.0080494] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/14/2022] Open
Abstract
Recurrent fluorescence (RF) from isolated carbon clusters containing between 24 and 60 atoms is theoretically investigated as a function of internal energy, cluster size, and structural features. The vibrational relaxation kinetics and the associated IR emission spectra are determined by means of a Monte Carlo approach with vibrational density of states computed in the harmonic approximation. RF is generally found to be highly competitive with vibrational emission. The behaviors predicted for clusters of various sizes and archetypal structures indicate that the IR emission spectra are strongly influenced by RF, an energy gap law being obtained for the evolution of the RF rate constant depending on the electronic excitation state. The present results are relevant to the photophysics of the interstellar medium and could contribute to elucidating the carriers of the extended red emission bands and the continuum emission lying below the aromatic infrared bands believed to originate from mixed aromatic–aliphatic compounds.
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Affiliation(s)
- O. Lacinbala
- Université Paris-Saclay, CNRS, Institut des Sciences Moléculaires d’Orsay (ISMO), 91405 Orsay, France
| | - F. Calvo
- Université Grenoble-Alpes, CNRS, LIPhy, 38000 Grenoble, France
| | - C. Dubosq
- Laboratoire de Chimie et Physique Quantiques (LCPQ), Fédération FeRMI, Université de Toulouse, CNRS, 31062 Toulouse, France
| | - C. Falvo
- Université Paris-Saclay, CNRS, Institut des Sciences Moléculaires d’Orsay (ISMO), 91405 Orsay, France
- Université Grenoble-Alpes, CNRS, LIPhy, 38000 Grenoble, France
| | - P. Parneix
- Université Paris-Saclay, CNRS, Institut des Sciences Moléculaires d’Orsay (ISMO), 91405 Orsay, France
| | - M. Rapacioli
- Laboratoire de Chimie et Physique Quantiques (LCPQ), Fédération FeRMI, Université de Toulouse, CNRS, 31062 Toulouse, France
| | - A. Simon
- Laboratoire de Chimie et Physique Quantiques (LCPQ), Fédération FeRMI, Université de Toulouse, CNRS, 31062 Toulouse, France
| | - T. Pino
- Université Paris-Saclay, CNRS, Institut des Sciences Moléculaires d’Orsay (ISMO), 91405 Orsay, France
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6
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Bernard J, Al-Mogeeth A, Martin S, Montagne G, Joblin C, Dontot L, Spiegelman F, Rapacioli M. Experimental and theoretical study of photo-dissociation spectroscopy of pyrene dimer radical cations stored in a compact electrostatic ion storage ring. Phys Chem Chem Phys 2021; 23:6017-6028. [PMID: 33667290 DOI: 10.1039/d0cp05779g] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/21/2022]
Abstract
In this paper, we present an experimental and theoretical study of the photo-dissociation of free-flying dimer radical cations of pyrene (C16H10)2+. Experimentally, the dimers were produced in the plasma of an electron cyclotron resonance ion source and stored in an electrostatic ion storage ring, the Mini-Ring for times up to 10 ms and the photo-dissociation spectrum was recorded in the 400 to 2000 nm range. Two broad absorption bands were observed at 550 (2.25 eV) and 1560 nm (0.79 eV), respectively. Theoretical simulations of the absorption spectrum as a function of the temperature were performed using the Density Functional based Tight Binding approach within the Extended Configuration Interaction scheme (DFTB-EXCI) to determine the electronic structure. The simulation involved all excited electronic states correlated asymptotically with the five lowest excited states D1-D5 of the monomer cation and a Monte Carlo exploration of the electronic ground state potential energy surface. The simulations exhibit three major bands at 1.0, 2.1 and 2.8 eV respectively. They allow assigning the experimental band at 1560 nm to absorption by the charge resonance (CR) excited state correlated with the ground state of the monomer D0. The band at 550 nm is tentatively attributed to dimer states correlated with excited states D2-D4, in the monomer cation. Simulations also show that the CR band broadens and shifts towards longer wavelength with increasing temperature. It results from the dependence on the geometry of the energy gap between the ground state and the lowest excited state. The comparison of the experimental spectrum with theoretical spectra at various temperatures allows us to estimate the temperature of the stored (C16H10)2+ in the 300-400 K range, which is also in line with the expected temperatures of the ions deduced from the analysis of the natural decay curve.
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Affiliation(s)
- J Bernard
- Institut Lumière Matière, UMR5306 Université Lyon 1-CNRS, Université de Lyon, 69622 Villeurbanne cedex, France.
| | - A Al-Mogeeth
- Institut Lumière Matière, UMR5306 Université Lyon 1-CNRS, Université de Lyon, 69622 Villeurbanne cedex, France.
| | - S Martin
- Institut Lumière Matière, UMR5306 Université Lyon 1-CNRS, Université de Lyon, 69622 Villeurbanne cedex, France.
| | - G Montagne
- Institut Lumière Matière, UMR5306 Université Lyon 1-CNRS, Université de Lyon, 69622 Villeurbanne cedex, France.
| | - C Joblin
- Institut de Recherche en Astrophysique et Planétologie, Université de Toulouse (UPS), CNRS, CNES, 9 Avenue du Colonel Roche, F-31028 Toulouse, France
| | - L Dontot
- Laboratoire de Chimie et de Physique Quantiques (LCPQ), IRSAMC, Université de Toulouse (UPS) and CNRS, 118 Route de Narbonne, F-31062 Toulouse, France
| | - F Spiegelman
- Laboratoire de Chimie et de Physique Quantiques (LCPQ), IRSAMC, Université de Toulouse (UPS) and CNRS, 118 Route de Narbonne, F-31062 Toulouse, France
| | - M Rapacioli
- Laboratoire de Chimie et de Physique Quantiques (LCPQ), IRSAMC, Université de Toulouse (UPS) and CNRS, 118 Route de Narbonne, F-31062 Toulouse, France
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7
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Stockett MH, Bull JN, Buntine JT, Carrascosa E, Ji M, Kono N, Schmidt HT, Zettergren H. Unimolecular fragmentation and radiative cooling of isolated PAH ions: A quantitative study. J Chem Phys 2020; 153:154303. [PMID: 33092387 DOI: 10.1063/5.0027773] [Citation(s) in RCA: 8] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/14/2022] Open
Abstract
Time-resolved spontaneous and laser-induced unimolecular fragmentation of perylene cations (C20H12 +) has been measured on timescales up to 2 s in a cryogenic electrostatic ion beam storage ring. We elaborate a quantitative model, which includes fragmentation in competition with radiative cooling via both vibrational and electronic (recurrent fluorescence) de-excitation. Excellent agreement with experimental results is found when sequential fragmentation of daughter ions co-stored with the parent perylene ions is included in the model. Based on the comparison of the model to experiment, we constrain the oscillator strength of the D1 → D0 emissive electronic transition in perylene (fRF = 0.055 ± 0.011), as well as the absolute absorption cross section of the D5 ← D0 excitation transition (σabs > 670 Mb). The former transition is responsible for the laser-induced and recurrent fluorescence of perylene, and the latter is the most prominent in the absorption spectrum. The vibrational cooling rate is found to be consistent with the simple harmonic cascade approximation. Quantitative experimental benchmarks of unimolecular processes in polycyclic aromatic hydrocarbon ions like perylene are important for refining astrochemical models.
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Affiliation(s)
- Mark H Stockett
- Department of Physics, Stockholm University, SE-10691 Stockholm, Sweden
| | - James N Bull
- School of Chemistry, University of East Anglia, Norwich Research Park, Norwich NR4 7TJ, United Kingdom
| | - Jack T Buntine
- School of Chemistry, University of Melbourne, Parkville, VIC 3010, Australia
| | - Eduardo Carrascosa
- Laboratoire de Chimie Physique Moléculaire, École Polytechnique Fédérale de Lausanne, EPFL SB ISIC LCPM, Station 6, CH-1015 Lausanne, Switzerland
| | - MingChao Ji
- Department of Physics, Stockholm University, SE-10691 Stockholm, Sweden
| | - Naoko Kono
- Department of Physics, Stockholm University, SE-10691 Stockholm, Sweden
| | - Henning T Schmidt
- Department of Physics, Stockholm University, SE-10691 Stockholm, Sweden
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8
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Ferrari P, Janssens E, Lievens P, Hansen K. Radiative cooling of size-selected gas phase clusters. INT REV PHYS CHEM 2019. [DOI: 10.1080/0144235x.2019.1678929] [Citation(s) in RCA: 8] [Impact Index Per Article: 1.6] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/25/2022]
Affiliation(s)
- Piero Ferrari
- Quantum Solid State Physics, Department of Physics and Astronomy, Faculty of Science, KU Leuven, Leuven, Belgium
| | - Ewald Janssens
- Quantum Solid State Physics, Department of Physics and Astronomy, Faculty of Science, KU Leuven, Leuven, Belgium
| | - Peter Lievens
- Quantum Solid State Physics, Department of Physics and Astronomy, Faculty of Science, KU Leuven, Leuven, Belgium
| | - Klavs Hansen
- Center for Joint Quantum Studies and Department of Physics, School of Science, Tianjin University, Tianjin, People's Republic of China
- Department of Physics, University of Gothenburg, Gothenburg, Sweden
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9
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Bull JN, Scholz MS, Carrascosa E, Kristiansson MK, Eklund G, Punnakayathil N, de Ruette N, Zettergren H, Schmidt HT, Cederquist H, Stockett MH. Ultraslow radiative cooling of Cn− (n = 3–5). J Chem Phys 2019; 151:114304. [DOI: 10.1063/1.5114678] [Citation(s) in RCA: 9] [Impact Index Per Article: 1.8] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/14/2022] Open
Affiliation(s)
- James N. Bull
- School of Chemistry, Norwich Research Park, University of East Anglia, Norwich NR4 7TJ, United Kingdom
| | - Michael S. Scholz
- School of Chemistry, University of Melbourne, Parkville, VIC 3010, Australia
| | - Eduardo Carrascosa
- Laboratoire de Chimie Physique Moléculaire, École Polytechnique Fédérale de Lausanne, EPFL SB ISIC LCPM, Station 6, CH-1015 Lausanne, Switzerland
| | | | - Gustav Eklund
- Department of Physics, Stockholm University, SE-10691 Stockholm, Sweden
| | | | | | | | | | - Henrik Cederquist
- Department of Physics, Stockholm University, SE-10691 Stockholm, Sweden
| | - Mark H. Stockett
- Department of Physics, Stockholm University, SE-10691 Stockholm, Sweden
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10
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Zhu GZ, Cheung LF, Liu Y, Qian CH, Wang LS. Resonant Two-Photon Photoelectron Imaging and Intersystem Crossing from Excited Dipole-Bound States of Cold Anions. J Phys Chem Lett 2019; 10:4339-4344. [PMID: 31314535 DOI: 10.1021/acs.jpclett.9b01743] [Citation(s) in RCA: 16] [Impact Index Per Article: 3.2] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 06/10/2023]
Abstract
We report the observation of a dipole-bound state (DBS) 659 cm-1 below the electron detachment threshold of cryogenically cooled deprotonated 4,4'-biphenol anion (bPh-) and 19 of its lowest vibrational levels. Resonant two-photon photoelectron imaging (R2P-PEI) via the vibrational levels of the DBS displays a sharp peak with a constant binding energy. This observation indicates vertical detachment from the vibrational levels of the DBS to the corresponding neutral levels with the conservation of the vibrational energy, suggesting that the highly diffuse electron in the DBS has little effect on the neutral core. The R2P-PEI spectra also exhibit two features at lower binding energies, which come from intersystem crossings from the DBS to two lower-lying valence-bound triplet excited states of bPh-. The current study discloses the first R2P-PEI spectra from vibrational excited states of a DBS and direct spectroscopic evidence of transitions from a DBS to valence-bound states of anions.
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Affiliation(s)
- Guo-Zhu Zhu
- Department of Chemistry , Brown University , Providence , Rhode Island 02912 , United States
| | - Ling Fung Cheung
- Department of Chemistry , Brown University , Providence , Rhode Island 02912 , United States
| | - Yuan Liu
- Department of Chemistry , Brown University , Providence , Rhode Island 02912 , United States
| | - Chen-Hui Qian
- Department of Chemistry , Brown University , Providence , Rhode Island 02912 , United States
| | - Lai-Sheng Wang
- Department of Chemistry , Brown University , Providence , Rhode Island 02912 , United States
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11
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Hansen K, Ferrari P. Influence of thermal radiation on hot cluster decay rates and abundances. CHINESE J CHEM PHYS 2019. [DOI: 10.1063/1674-0068/cjcp1812262] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.4] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/14/2022]
Affiliation(s)
- Klavs Hansen
- Center for Joint Quantum Studies and Department of Physics, Tianjin University, Tianjin 300072, China
- Department of Physics, Gothenburg University, Gothenburg 41296, Sweden
| | - P. Ferrari
- Laboratory of Solid State Physics and Magnetism, KU Leuven, Leuven 3001, Belgium
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12
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Bernard J, Al-Mogeeth A, Allouche AR, Chen L, Montagne G, Martin S. Photo-dissociation of naphthalene dimer cations stored in a compact electrostatic ion storage ring. J Chem Phys 2019; 150:054303. [PMID: 30736693 DOI: 10.1063/1.5055939] [Citation(s) in RCA: 6] [Impact Index Per Article: 1.2] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/14/2022] Open
Abstract
Naphthalene dimer cations [C10H8]2 + have been produced by using an electron cyclotron resonance plasma ion source and stored in a compact electrostatic ion storage ring. We show that the radiative cooling of these cations is much slower than the isolated monomer naphthalene cations. We also report on photo-dissociation studies in the gas phase of naphthalene dimer cations at high internal energy. The dissociation energy is estimated to 0.5 eV in close agreement with previous measurements but a factor of 2 smaller than recent (density functional theory (DFT) and ab initio) theoretical studies. As uncertainties on theory as well as on the experiment cannot be as large as this difference, we conclude that this discrepancy may be due to temperature effects with possible isomerization. As an interpretation of the photo-dissociation spectrum of naphthalene dimer cations, we propose a tentative simple analytical model based on effective Morse potentials. These effective potentials are expected to "average" temperature effects that would apparently result in a smaller energy difference between the fundamental and dissociation states due to the twisting vibration modes of the naphthalene dimer cations.
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Affiliation(s)
- J Bernard
- Institut Lumière Matière, UMR5306 Université Lyon 1-CNRS, Université de Lyon, Villeurbanne Cedex 69622, France
| | - A Al-Mogeeth
- Institut Lumière Matière, UMR5306 Université Lyon 1-CNRS, Université de Lyon, Villeurbanne Cedex 69622, France
| | - A-R Allouche
- Institut Lumière Matière, UMR5306 Université Lyon 1-CNRS, Université de Lyon, Villeurbanne Cedex 69622, France
| | - L Chen
- Institut Lumière Matière, UMR5306 Université Lyon 1-CNRS, Université de Lyon, Villeurbanne Cedex 69622, France
| | - G Montagne
- Institut Lumière Matière, UMR5306 Université Lyon 1-CNRS, Université de Lyon, Villeurbanne Cedex 69622, France
| | - S Martin
- Institut Lumière Matière, UMR5306 Université Lyon 1-CNRS, Université de Lyon, Villeurbanne Cedex 69622, France
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13
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Chen FQ, Kono N, Suzuki R, Furukawa T, Tanuma H, Ferrari P, Azuma T, Matsumoto J, Shiromaru H, Zhaunerchyk V, Hansen K. Radiative cooling of cationic carbon clusters, C N+, N = 8, 10, 13-16. Phys Chem Chem Phys 2019; 21:1587-1596. [PMID: 30620033 DOI: 10.1039/c8cp06368k] [Citation(s) in RCA: 5] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/18/2022]
Abstract
The radiative cooling of highly excited carbon cluster cations of sizes N = 8, 10, 13-16 has been studied in an electrostatic storage ring. The cooling rate constants vary with cluster size from a maximum at N = 8 of 2.6 × 104 s-1 and a minimum at N = 13 of 4.4 × 103 s-1. The high rates indicate that photon emission takes place from electronically excited ions, providing a strong stabilizing cooling of the molecules.
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Affiliation(s)
- F-Q Chen
- School of Materials Science and Engineering, Tianjin University, Tianjin 300350, China
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14
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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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15
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Chartkunchand KC, Stockett MH, Anderson EK, Eklund G, Kristiansson MK, Kamińska M, de Ruette N, Blom M, Björkhage M, Källberg A, Löfgren P, Reinhed P, Rosén S, Simonsson A, Zettergren H, Schmidt HT, Cederquist H. Dianion diagnostics in DESIREE: High-sensitivity detection of C n2- from a sputter ion source. THE REVIEW OF SCIENTIFIC INSTRUMENTS 2018; 89:033112. [PMID: 29604753 DOI: 10.1063/1.5010077] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 06/08/2023]
Abstract
A sputter ion source with a solid graphite target has been used to produce dianions with a focus on carbon cluster dianions, Cn2-, with n = 7-24. Singly and doubly charged anions from the source were accelerated together to kinetic energies of 10 keV per atomic unit of charge and injected into one of the cryogenic (13 K) ion-beam storage rings of the Double ElectroStatic Ion Ring Experiment facility at Stockholm University. Spontaneous decay of internally hot Cn2- dianions injected into the ring yielded Cn- anions with kinetic energies of 20 keV, which were counted with a microchannel plate detector. Mass spectra produced by scanning the magnetic field of a 90° analyzing magnet on the ion injection line reflect the production of internally hot C72- - C242- dianions with lifetimes in the range of tens of microseconds to milliseconds. In spite of the high sensitivity of this method, no conclusive evidence of C62- was found while there was a clear C72- signal with the expected isotopic distribution. This is consistent with earlier experimental studies and with theoretical predictions. An upper limit is deduced for a C62- signal that is two orders-of-magnitude smaller than that for C72-. In addition, CnO2- and CnCu2- dianions were detected.
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Affiliation(s)
- K C Chartkunchand
- Department of Physics, Stockholm University, AlbaNova, SE-106 91 Stockholm, Sweden
| | - M H Stockett
- Department of Physics, Stockholm University, AlbaNova, SE-106 91 Stockholm, Sweden
| | - E K Anderson
- Department of Physics, Stockholm University, AlbaNova, SE-106 91 Stockholm, Sweden
| | - G Eklund
- Department of Physics, Stockholm University, AlbaNova, SE-106 91 Stockholm, Sweden
| | - M K Kristiansson
- Department of Physics, Stockholm University, AlbaNova, SE-106 91 Stockholm, Sweden
| | - M Kamińska
- Department of Physics, Stockholm University, AlbaNova, SE-106 91 Stockholm, Sweden
| | - N de Ruette
- Department of Physics, Stockholm University, AlbaNova, SE-106 91 Stockholm, Sweden
| | - M Blom
- Department of Physics, Stockholm University, AlbaNova, SE-106 91 Stockholm, Sweden
| | - M Björkhage
- Department of Physics, Stockholm University, AlbaNova, SE-106 91 Stockholm, Sweden
| | - A Källberg
- Department of Physics, Stockholm University, AlbaNova, SE-106 91 Stockholm, Sweden
| | - P Löfgren
- Department of Physics, Stockholm University, AlbaNova, SE-106 91 Stockholm, Sweden
| | - P Reinhed
- Department of Physics, Stockholm University, AlbaNova, SE-106 91 Stockholm, Sweden
| | - S Rosén
- Department of Physics, Stockholm University, AlbaNova, SE-106 91 Stockholm, Sweden
| | - A Simonsson
- Department of Physics, Stockholm University, AlbaNova, SE-106 91 Stockholm, Sweden
| | - H Zettergren
- Department of Physics, Stockholm University, AlbaNova, SE-106 91 Stockholm, Sweden
| | - H T Schmidt
- Department of Physics, Stockholm University, AlbaNova, SE-106 91 Stockholm, Sweden
| | - H Cederquist
- Department of Physics, Stockholm University, AlbaNova, SE-106 91 Stockholm, Sweden
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16
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Skomorowski W, Gulania S, Krylov AI. Bound and continuum-embedded states of cyanopolyyne anions. Phys Chem Chem Phys 2018; 20:4805-4817. [DOI: 10.1039/c7cp08227d] [Citation(s) in RCA: 21] [Impact Index Per Article: 3.5] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/21/2022]
Abstract
Equation-of-motion coupled-cluster calculations reveal systematic trends across bound and continuum-embedded excited states in cyanopolyyne anions.
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Affiliation(s)
| | - Sahil Gulania
- Department of Chemistry
- University of Southern California
- Los Angeles
- USA
| | - Anna I. Krylov
- Department of Chemistry
- University of Southern California
- Los Angeles
- USA
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17
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Ferrari P, Hansen K, Lievens P, Janssens E. Stability of small cationic platinum clusters. Phys Chem Chem Phys 2018; 20:29085-29090. [DOI: 10.1039/c8cp06092d] [Citation(s) in RCA: 8] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/21/2022]
Abstract
The relative stability of small cationic platinum clusters is investigated by photofragmentation experiments and density functional theory calculations.
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Affiliation(s)
- Piero Ferrari
- Laboratory of Solid State Physics and Magnetism
- KU Leuven
- 3001 Leuven
- Belgium
| | - Klavs Hansen
- Center for Joint Quantum Studies and Department of Physics
- Tianjin University
- 300072 Tianjin
- China
- Department of Physics
| | - Peter Lievens
- Laboratory of Solid State Physics and Magnetism
- KU Leuven
- 3001 Leuven
- Belgium
| | - Ewald Janssens
- Laboratory of Solid State Physics and Magnetism
- KU Leuven
- 3001 Leuven
- Belgium
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18
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Chandrasekaran V, Prabhakaran A, Kafle B, Rubinstein H, Heber O, Rappaport M, Toker Y, Zajfman D. Formation and stabilization of C6− by radiative electron attachment. J Chem Phys 2017. [DOI: 10.1063/1.4977059] [Citation(s) in RCA: 8] [Impact Index Per Article: 1.1] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/14/2022] Open
Affiliation(s)
- Vijayanand Chandrasekaran
- Department of Particle Physics and Astrophysics, Weizmann Institute of Science, Rehovot 76100, Israel
| | - Aneesh Prabhakaran
- Department of Particle Physics and Astrophysics, Weizmann Institute of Science, Rehovot 76100, Israel
| | - Bhim Kafle
- Department of Particle Physics and Astrophysics, Weizmann Institute of Science, Rehovot 76100, Israel
| | - Hilel Rubinstein
- Department of Particle Physics and Astrophysics, Weizmann Institute of Science, Rehovot 76100, Israel
| | - Oded Heber
- Department of Particle Physics and Astrophysics, Weizmann Institute of Science, Rehovot 76100, Israel
| | - Michael Rappaport
- Department of Particle Physics and Astrophysics, Weizmann Institute of Science, Rehovot 76100, Israel
| | - Yoni Toker
- Department of Particle Physics and Astrophysics, Weizmann Institute of Science, Rehovot 76100, Israel
| | - Daniel Zajfman
- Department of Particle Physics and Astrophysics, Weizmann Institute of Science, Rehovot 76100, Israel
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19
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Ji M, Bernard J, Chen L, Brédy R, Ortéga C, Joblin C, Cassimi A, Martin S. Cooling of isolated anthracene cations probed with photons of different wavelengths in the Mini-Ring. J Chem Phys 2017; 146:044301. [PMID: 28147509 DOI: 10.1063/1.4973651] [Citation(s) in RCA: 11] [Impact Index Per Article: 1.6] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/14/2022] Open
Abstract
We report on a direct measurement of the Internal Energy Distribution (IED) shift rate of an initially hot polycyclic aromatic hydrocarbon (PAH) molecular ensemble, anthracene cations (C14H10+). The ions were produced in an electron cyclotron resonance (ECR) ion source and stored in an electrostatic ion storage ring, the Mini-Ring. Laser pulses of two wavelengths were sent successively to merge the stored ion bunch at different storage times to enhance the neutral fragment yield due to fast laser induced dissociation. Using this technique, we have been able to determine directly the energy shift rate of the IED, without involving any theoretical simulation or any assumption on dissociation rates, cooling rates, or the initial IED. Theoretical energy shift rates have been estimated from the evolution of simulated IEDs by taking into account the effects of the unimolecular dissociation and two radiative decay mechanisms: the Poincaré fluorescence and the infrared vibrational emission. The comparison between the experimental results and the model provides new evidence of the important role of the Poincaré fluorescence in the overall cooling process of anthracene cations. Although in the short time range the commonly accepted intuition says that the cooling would result mostly from the dissociation of the hottest ions (depletion cooling), we demonstrate that the Poincaré fluorescence is the dominant contribution (about 85%) to the net cooling effect.
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Affiliation(s)
- M Ji
- Institut Lumière Matière, UMR 5306 Université Lyon 1-CNRS, Université de Lyon, 69622 Cedex Villeurbanne, France
| | - J Bernard
- Institut Lumière Matière, UMR 5306 Université Lyon 1-CNRS, Université de Lyon, 69622 Cedex Villeurbanne, France
| | - L Chen
- Institut Lumière Matière, UMR 5306 Université Lyon 1-CNRS, Université de Lyon, 69622 Cedex Villeurbanne, France
| | - R Brédy
- Institut Lumière Matière, UMR 5306 Université Lyon 1-CNRS, Université de Lyon, 69622 Cedex Villeurbanne, France
| | - C Ortéga
- Institut Lumière Matière, UMR 5306 Université Lyon 1-CNRS, Université de Lyon, 69622 Cedex Villeurbanne, France
| | - C Joblin
- Université de Toulouse; UPS-OMP; IRAP; Toulouse, France
| | - A Cassimi
- CIMAP, CEA/CNRS/ENSICAEN/UNICAEN, Bd H. Becquerel, BP 5133, F-14070 Caen, France
| | - S Martin
- Institut Lumière Matière, UMR 5306 Université Lyon 1-CNRS, Université de Lyon, 69622 Cedex Villeurbanne, France
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20
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Jones AP. Dust evolution, a global view: II. Top-down branching, nanoparticle fragmentation and the mystery of the diffuse interstellar band carriers. ROYAL SOCIETY OPEN SCIENCE 2016; 3:160223. [PMID: 28083089 PMCID: PMC5210671 DOI: 10.1098/rsos.160223] [Citation(s) in RCA: 4] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Subscribe] [Scholar Register] [Received: 03/29/2016] [Accepted: 11/01/2016] [Indexed: 05/25/2023]
Abstract
The origin of the diffuse interstellar bands (DIBs), one of the longest-standing mysteries of the interstellar medium (ISM), is explored within the framework of The Heterogeneous dust Evolution Model for Interstellar Solids (THEMIS). The likely nature of the DIB carriers and their evolution is here explored within the framework of the structures and sub-structures inherent to doped hydrogenated amorphous carbon grains in the ISM. Based on the natural aromatic-rich moieties (asphaltenes) recovered from coal and oil, the likely structure of their interstellar analogues is investigated within the context of the diffuse band problem. It is here proposed that the top-down evolution of interstellar carbonaceous grains, and, in particular, a-C(:H) nanoparticles, is at the heart of the formation and evolution of the DIB carriers and their associations with small molecules and radicals, such as C2, C3, CH and CN. It is most probable that the DIBs are carried by dehydrogenated, ionized, hetero-cyclic, olefinic and aromatic-rich moieties that form an integral part of the contiguous structure of hetero-atom-doped hydrogenated amorphous carbon nanoparticles and their daughter fragmentation products. Within this framework, it is proposed that polyene structures in all their variants could be viable DIB carrier candidates.
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Affiliation(s)
- A. P. Jones
- Institut d’Astrophysique Spatiale, CNRS, Univ. Paris-Sud, Université Paris-Saclay, Bât. 121, 91405 Orsay cedex, France
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21
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Jones AP. Dust evolution, a global view I. Nanoparticles, nascence, nitrogen and natural selection … joining the dots. ROYAL SOCIETY OPEN SCIENCE 2016; 3:160221. [PMID: 28083088 PMCID: PMC5210670 DOI: 10.1098/rsos.160221] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.4] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Subscribe] [Scholar Register] [Received: 03/29/2016] [Accepted: 11/14/2016] [Indexed: 05/25/2023]
Abstract
The role and importance of nanoparticles for interstellar chemistry and beyond is explored within the framework of The Heterogeneous dust Evolution Model for Interstellar Solids (THEMIS), focusing on their active surface chemistry, the effects of nitrogen doping and the natural selection of interesting nanoparticle sub-structures. Nanoparticle-driven chemistry, and in particular the role of intrinsic epoxide-type structures, could provide a viable route to the observed gas phase OH in tenuous interstellar clouds en route to becoming molecular clouds. The aromatic-rich moieties present in asphaltenes probably provide a viable model for the structures present within aromatic-rich interstellar carbonaceous grains. The observed doping of such nanoparticle structures with nitrogen, if also prevalent in interstellar dust, could perhaps have important and observable consequences for surface chemistry and the formation of precursor pre-biotic species.
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Affiliation(s)
- A. P. Jones
- Institut d’Astrophysique Spatiale, CNRS, Univ. Paris-Sud, Université Paris-Saclay, Bât. 121, 91405 Orsay cedex, France
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22
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Ebara Y, Furukawa T, Matsumoto J, Tanuma H, Azuma T, Shiromaru H, Hansen K. Detection of Recurrent Fluorescence Photons. PHYSICAL REVIEW LETTERS 2016; 117:133004. [PMID: 27715134 DOI: 10.1103/physrevlett.117.133004] [Citation(s) in RCA: 13] [Impact Index Per Article: 1.6] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Received: 02/10/2016] [Indexed: 06/06/2023]
Abstract
We have detected visible photons emitted from the thermally populated electronic excited state, namely recurrent fluorescence (RF), of C_{6}^{-} stored in an electrostatic ion storage ring. Clear evidence is provided to distinguish RF from normal fluorescence, based on the temporal profile of detected photons synchronized with the revolution of C_{6}^{-} in the ring, for which the time scale is far longer than the lifetime of the intact photoexcited state. The relaxation (cooling) process via RF is likely to be commonplace for isolated molecular systems and crucial to the stabilization of molecules in interstellar environments.
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Affiliation(s)
- Yuta Ebara
- Department of Physics, Tokyo Metropolitan University, Hachioji, Tokyo 192-0397, Japan
| | - Takeshi Furukawa
- Department of Physics, Tokyo Metropolitan University, Hachioji, Tokyo 192-0397, Japan
| | - Jun Matsumoto
- Department of Chemistry, Tokyo Metropolitan University, Hachioji, Tokyo 192-0397, Japan
| | - Hajime Tanuma
- Department of Physics, Tokyo Metropolitan University, Hachioji, Tokyo 192-0397, Japan
| | - Toshiyuki Azuma
- Department of Physics, Tokyo Metropolitan University, Hachioji, Tokyo 192-0397, Japan
- Atomic, Molecular and Optical Physics Laboratory, RIKEN, 2-1 Hirosawa, Wako, Saitama 351-0198, Japan
| | - Haruo Shiromaru
- Department of Chemistry, Tokyo Metropolitan University, Hachioji, Tokyo 192-0397, Japan
| | - Klavs Hansen
- Department of Physics, University of Gothenburg 41296 Gothenburg, Sweden
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23
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Svendsen A, Teiwes R, Kiefer HV, Andersen LH, Pedersen HB. Analysis of ionic photofragments stored in an electrostatic storage ring. THE REVIEW OF SCIENTIFIC INSTRUMENTS 2016; 87:013111. [PMID: 26827313 DOI: 10.1063/1.4940423] [Citation(s) in RCA: 5] [Impact Index Per Article: 0.6] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 06/05/2023]
Abstract
A new method to analyze the properties of fragment ions created in storage ring experiments is presented. The technique relies on an acceleration of ionic fragments immediately after production whereby the fragments are stored in the storage ring. To obtain a fragment mass spectrum, the storage ring is exploited as an electrostatic analyzer (ESA) in which case the number of stored fragment ions is recorded as a function of the applied acceleration potential. However, the storage ring can additionally be employed as a time-of-flight (TOF) instrument by registering the temporal distribution of fragment ions. It is demonstrated that the combined ESA-TOF operation of the ring allows not only to determine fragment masses with much better resolution compared to the ESA mode alone but also enables the extraction of detailed information on the fragmentation dynamics. The method is described analytically and verified with photodissociation experiments on stored Cl2 (-) at an excitation wavelength of 530 nm.
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Affiliation(s)
- Annette Svendsen
- Department of Physics and Astronomy, Aarhus University, DK-8000 Aarhus C, Denmark
| | - Ricky Teiwes
- Department of Physics and Astronomy, Aarhus University, DK-8000 Aarhus C, Denmark
| | - Hjalte V Kiefer
- Department of Physics and Astronomy, Aarhus University, DK-8000 Aarhus C, Denmark
| | - Lars H Andersen
- Department of Physics and Astronomy, Aarhus University, DK-8000 Aarhus C, Denmark
| | - Henrik B Pedersen
- Department of Physics and Astronomy, Aarhus University, DK-8000 Aarhus C, Denmark
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24
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Ferrari P, Janssens E, Lievens P, Hansen K. Thermal radiation and fragmentation pathways of photo-excited silicon clusters. J Chem Phys 2015; 143:224313. [PMID: 26671381 DOI: 10.1063/1.4936917] [Citation(s) in RCA: 12] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/15/2022] Open
Abstract
The fragmentation of laser heated silicon clusters was studied by time-of-flight mass spectrometry. For Si(n)(+) (n = 5-19, 21), the lowest energy fragmentation pathways were identified as the metastable decay channel occurring after the primary acceleration of the ions. The radiative cooling of laser excited Si(n)(+) (n = 5-9, 11, and 13) was quantified via its quenching effect on the amount of metastable fragmentation. The quenching varied strongly with cluster size, from no observable amount for Si7(+) to a cooling constant of 3 ⋅ 10(5) s(-1) for Si13(+). In addition, based on the observed fragmentation channels, the ionization energies and the relative binding energies of the clusters were partially ordered, and several ionization energies have been bracketed more precisely.
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Affiliation(s)
- Piero Ferrari
- Laboratory of Solid State Physics and Magnetism, KU Leuven, 3001 Leuven, Belgium
| | - Ewald Janssens
- Laboratory of Solid State Physics and Magnetism, KU Leuven, 3001 Leuven, Belgium
| | - Peter Lievens
- Laboratory of Solid State Physics and Magnetism, KU Leuven, 3001 Leuven, Belgium
| | - Klavs Hansen
- Department of Physics, University of Gothenburg, 41296 Gothenburg, Sweden and Department of Physics and Astronomy, Aarhus University, 8000 Aarhus C, Denmark
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25
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Kono N, Furukawa T, Tanuma H, Matsumoto J, Shiromaru H, Azuma T, Najafian K, Pettersson MS, Dynefors B, Hansen K. Inverse internal conversion in C4− below the electron detachment threshold. Phys Chem Chem Phys 2015; 17:24732-7. [DOI: 10.1039/c5cp02549d] [Citation(s) in RCA: 27] [Impact Index Per Article: 3.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/21/2022]
Abstract
Inverse internal conversion below the electron detachment threshold drives fast the radiative cooling of vibrationally hot C4− isolated in a vacuum.
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Affiliation(s)
- Naoko Kono
- Department of Physics
- Tokyo Metropolitan University
- Hachiouji-shi
- Japan
| | - Takeshi Furukawa
- Department of Physics
- Tokyo Metropolitan University
- Hachiouji-shi
- Japan
| | - Hajime Tanuma
- Department of Physics
- Tokyo Metropolitan University
- Hachiouji-shi
- Japan
| | - Jun Matsumoto
- Department of Chemistry
- Tokyo Metropolitan University
- Hachiouji-shi
- Japan
| | - Haruo Shiromaru
- Department of Chemistry
- Tokyo Metropolitan University
- Hachiouji-shi
- Japan
| | - Toshiyuki Azuma
- Atomic, Molecular & Optical Physics Laboratory
- RIKEN
- Wako-shi
- Japan
| | - Kaveh Najafian
- Department of Physics
- University of Gothenburg
- 41296 Gothenburg
- Sweden
| | | | - Bertil Dynefors
- Applied Physics
- Chalmers Technical University
- 41296 Gothenburg
- Sweden
| | - Klavs Hansen
- Department of Physics
- University of Gothenburg
- 41296 Gothenburg
- Sweden
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26
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Chandrasekaran V, Kafle B, Prabhakaran A, Heber O, Rappaport M, Rubinstein H, Schwalm D, Toker Y, Zajfman D. [Not Available]. J Phys Chem Lett 2014; 5:4078-82. [PMID: 26278935 DOI: 10.1021/jz502100z] [Citation(s) in RCA: 20] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 05/16/2023]
Affiliation(s)
- Vijayanand Chandrasekaran
- †Department of Particle Physics and Astrophysics, Weizmann Institute of Science, Rehovot, 76100, Israel
| | - Bhim Kafle
- †Department of Particle Physics and Astrophysics, Weizmann Institute of Science, Rehovot, 76100, Israel
| | - Aneesh Prabhakaran
- †Department of Particle Physics and Astrophysics, Weizmann Institute of Science, Rehovot, 76100, Israel
| | - Oded Heber
- †Department of Particle Physics and Astrophysics, Weizmann Institute of Science, Rehovot, 76100, Israel
| | - Michael Rappaport
- †Department of Particle Physics and Astrophysics, Weizmann Institute of Science, Rehovot, 76100, Israel
| | - Hilel Rubinstein
- †Department of Particle Physics and Astrophysics, Weizmann Institute of Science, Rehovot, 76100, Israel
| | - Dirk Schwalm
- †Department of Particle Physics and Astrophysics, Weizmann Institute of Science, Rehovot, 76100, Israel
- ‡Max-Planck-Institut für Kernphysik, D-69117 Heidelberg, Germany
| | - Yoni Toker
- †Department of Particle Physics and Astrophysics, Weizmann Institute of Science, Rehovot, 76100, Israel
| | - Daniel Zajfman
- †Department of Particle Physics and Astrophysics, Weizmann Institute of Science, Rehovot, 76100, Israel
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