1
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Schöpfer G, Bergmeister S, Ončák M, Stromberg I, Mahmoodi-Darian M, Scheier P, Echt O, Gruber E. Doubly charged dimers and trimers of heavy noble gases. Phys Chem Chem Phys 2024; 26:11482-11490. [PMID: 38533827 PMCID: PMC11022278 DOI: 10.1039/d4cp00465e] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/31/2024] [Accepted: 03/21/2024] [Indexed: 03/28/2024]
Abstract
Many doubly charged heteronuclear dimers are metastable or even thermodynamically stable with respect to charge separation. Homonuclear dicationic dimers, however, are more difficult to form. He22+ was the first noble gas dimer predicted to be metastable and, decades later, observed. Ne22+ is the only other dicationic noble gas dimer that has been detected so far. Here, we present a novel approach to form fragile dicationic species, by post-ionization of singly charged ions that are embedded in helium nanodroplets (HNDs). Bare ions are then extracted by colliding the HNDs with helium gas. We detect homonuclear doubly charged dimers and trimers of krypton and xenon, but not argon. Our multi-reference ab initio calculations confirm the stability of Kr22+, Kr32+, Xe22+, Xe32+, and Ar22+, but put the stability of Ar32+ towards dissociation to Ar+ + Ar2+ into question.
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Affiliation(s)
- Gabriel Schöpfer
- Institut für Ionenphysik und Angewandte Physik, Universität Innsbruck, Innsbruck, Austria.
| | - Stefan Bergmeister
- Institut für Ionenphysik und Angewandte Physik, Universität Innsbruck, Innsbruck, Austria.
| | - Milan Ončák
- Institut für Ionenphysik und Angewandte Physik, Universität Innsbruck, Innsbruck, Austria.
| | - Ianessa Stromberg
- Institut für Ionenphysik und Angewandte Physik, Universität Innsbruck, Innsbruck, Austria.
- School of Chemistry, University of Edinburgh, Edinburgh, UK
| | | | - Paul Scheier
- Institut für Ionenphysik und Angewandte Physik, Universität Innsbruck, Innsbruck, Austria.
| | - Olof Echt
- Institut für Ionenphysik und Angewandte Physik, Universität Innsbruck, Innsbruck, Austria.
- Department of Physics, University of New Hampshire, Durham, USA
| | - Elisabeth Gruber
- Institut für Ionenphysik und Angewandte Physik, Universität Innsbruck, Innsbruck, Austria.
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2
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De S, Abid AR, Asmussen JD, Ben Ltaief L, Sishodia K, Ulmer A, Pedersen HB, Krishnan SR, Mudrich M. Fragmentation of water clusters formed in helium nanodroplets by charge transfer and Penning ionization. J Chem Phys 2024; 160:094308. [PMID: 38445733 DOI: 10.1063/5.0194098] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/25/2023] [Accepted: 02/16/2024] [Indexed: 03/07/2024] Open
Abstract
Helium nanodroplets ("HNDs") are widely used for forming tailor-made clusters and molecular complexes in a cold, transparent, and weakly interacting matrix. The characterization of embedded species by mass spectrometry is often complicated by the fragmentation and trapping of ions in the HNDs. Here, we systematically study fragment ion mass spectra of HND-aggregated water and oxygen clusters following their ionization by charge transfer ionization ("CTI") and Penning ionization ("PEI"). While the efficiency of PEI of embedded clusters is lower than for CTI by about factor 10, both the mean sizes of detected water clusters and the relative yields of unprotonated cluster ions are significantly larger, making PEI a "soft ionization" scheme. However, the tendency of ions to remain bound to HNDs leads to a reduced detection efficiency for large HNDs containing >104 helium atoms. These results are instrumental in determining optimal conditions for mass spectrometry and photoionization spectroscopy of molecular complexes and clusters aggregated in HNDs.
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Affiliation(s)
- S De
- Quantum Center of Excellence for Diamond and Emergent Materials and Department of Physics, Indian Institute of Technology Madras, Chennai 600036, India
| | - A R Abid
- Department of Physics and Astronomy, Aarhus University, 8000 Aarhus C, Denmark
| | - J D Asmussen
- Department of Physics and Astronomy, Aarhus University, 8000 Aarhus C, Denmark
| | - L Ben Ltaief
- Department of Physics and Astronomy, Aarhus University, 8000 Aarhus C, Denmark
| | - K Sishodia
- Quantum Center of Excellence for Diamond and Emergent Materials and Department of Physics, Indian Institute of Technology Madras, Chennai 600036, India
| | - A Ulmer
- Department of Physics, Universität Hamburg, Luruper Chaussee 149, 22761 Hamburg, Germany
| | - H B Pedersen
- Department of Physics and Astronomy, Aarhus University, 8000 Aarhus C, Denmark
| | - S R Krishnan
- Quantum Center of Excellence for Diamond and Emergent Materials and Department of Physics, Indian Institute of Technology Madras, Chennai 600036, India
| | - M Mudrich
- Department of Physics and Astronomy, Aarhus University, 8000 Aarhus C, Denmark
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3
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Asmussen JD, Abid AR, Sundaralingam A, Bastian B, Sishodia K, De S, Ben Ltaief L, Krishnan S, Pedersen HB, Mudrich M. Secondary ionization of pyrimidine nucleobases and their microhydrated derivatives in helium nanodroplets. Phys Chem Chem Phys 2023; 25:24819-24828. [PMID: 37671772 DOI: 10.1039/d3cp02879h] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 09/07/2023]
Abstract
Radiation damage in biological systems by ionizing radiation is predominantly caused by secondary processes such as charge and energy transfer leading to the breaking of bonds in DNA. Here, we study the fragmentation of cytosine (Cyt) and thymine (Thy) molecules, clusters and microhydrated derivatives induced by direct and indirect ionization initiated by extreme-ultraviolet (XUV) irradiation. Photofragmentation mass spectra and photoelectron spectra of free Cyt and Thy molecules are compared with mass and electron spectra of Cyt/Thy clusters and microhydrated Cyt/Thy molecules formed by aggregation in superfluid helium (He) nanodroplets. Penning ionization after resonant excitation of the He droplets is generally found to cause less fragmentation compared to direct photoionization and charge-transfer ionization after photoionization of the He droplets. When Cyt/Thy molecules and oligomers are complexed with water molecules, their fragmentation is efficiently suppressed. However, a similar suppression of fragmentation is observed when homogeneous Cyt/Thy clusters are formed in He nanodroplets, indicating a general trend. Penning ionization electron spectra (PIES) of Cyt/Thy are broad and nearly featureless but PIES of their microhydrated derivatives point at a sequential ionization process ending in unfragmented microsolvated Cyt/Thy cations.
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Affiliation(s)
- Jakob D Asmussen
- Department of Physics and Astronomy, Aarhus University, 8000 Aarhus C, Denmark.
| | - Abdul R Abid
- Department of Physics and Astronomy, Aarhus University, 8000 Aarhus C, Denmark.
| | | | - Björn Bastian
- Department of Physics and Astronomy, Aarhus University, 8000 Aarhus C, Denmark.
| | - Keshav Sishodia
- Quantum Center of Excellence for Diamond and Emergent Materials and Department of Physics, Indian Institute of Technology Madras, Chennai 600036, India
| | - Subhendu De
- Quantum Center of Excellence for Diamond and Emergent Materials and Department of Physics, Indian Institute of Technology Madras, Chennai 600036, India
| | - Ltaief Ben Ltaief
- Department of Physics and Astronomy, Aarhus University, 8000 Aarhus C, Denmark.
| | - Sivarama Krishnan
- Quantum Center of Excellence for Diamond and Emergent Materials and Department of Physics, Indian Institute of Technology Madras, Chennai 600036, India
| | - Henrik B Pedersen
- Department of Physics and Astronomy, Aarhus University, 8000 Aarhus C, Denmark.
| | - Marcel Mudrich
- Department of Physics and Astronomy, Aarhus University, 8000 Aarhus C, Denmark.
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4
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Asmussen JD, Sishodia K, Bastian B, Abid AR, Ben Ltaief L, Pedersen HB, De S, Medina C, Pal N, Richter R, Fennel T, Krishnan S, Mudrich M. Electron energy loss and angular asymmetry induced by elastic scattering in superfluid helium nanodroplets. NANOSCALE 2023; 15:14025-14031. [PMID: 37559557 DOI: 10.1039/d3nr03295g] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 08/11/2023]
Abstract
Helium nanodroplets are ideal model systems to unravel the complex interaction of condensed matter with ionizing radiation. Here we study the effect of purely elastic electron scattering on angular and energy distributions of photoelectrons emitted from He nanodroplets of variable size (10-109 atoms per droplets). For large droplets, photoelectrons develop a pronounced anisotropy along the incident light beam due to a shadowing effect within the droplets. In contrast, the detected photoelectron spectra are only weakly perturbed. This opens up possibilities for photoelectron spectroscopy of dopants embedded in droplets provided they are smaller than the penetration depth of the light and the trapping range of emitted electrons in liquid helium.
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Affiliation(s)
- Jakob D Asmussen
- Department of Physics and Astronomy, Aarhus University, Denmark.
| | - Keshav Sishodia
- Quantum Center of Excellence for Diamond and Emergent Materials and Department of Physics, Indian Institute of Technology Madras, India
| | - Björn Bastian
- Department of Physics and Astronomy, Aarhus University, Denmark.
| | - Abdul R Abid
- Department of Physics and Astronomy, Aarhus University, Denmark.
| | | | | | - Subhendu De
- Quantum Center of Excellence for Diamond and Emergent Materials and Department of Physics, Indian Institute of Technology Madras, India
| | | | | | | | | | - Sivarama Krishnan
- Quantum Center of Excellence for Diamond and Emergent Materials and Department of Physics, Indian Institute of Technology Madras, India
| | - Marcel Mudrich
- Department of Physics and Astronomy, Aarhus University, Denmark.
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5
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Ben Ltaief L, Sishodia K, Mandal S, De S, Krishnan SR, Medina C, Pal N, Richter R, Fennel T, Mudrich M. Efficient Indirect Interatomic Coulombic Decay Induced by Photoelectron Impact Excitation in Large Pure Helium Nanodroplets. PHYSICAL REVIEW LETTERS 2023; 131:023001. [PMID: 37505945 DOI: 10.1103/physrevlett.131.023001] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Received: 03/02/2023] [Accepted: 06/05/2023] [Indexed: 07/30/2023]
Abstract
Ionization of matter by energetic radiation generally causes complex secondary reactions that are hard to decipher. Using large helium nanodroplets irradiated by extreme ultraviolet (XUV) photons, we show that the full chain of processes ensuing primary photoionization can be tracked in detail by means of high-resolution electron spectroscopy. We find that elastic and inelastic scattering of photoelectrons efficiently induces interatomic Coulombic decay (ICD) in the droplets. This type of indirect ICD even becomes the dominant process of electron emission in nearly the entire XUV range in large droplets with radius ≳40 nm. Indirect ICD processes induced by electron scattering likely play an important role in other condensed-phase systems exposed to ionizing radiation as well, including biological matter.
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Affiliation(s)
- L Ben Ltaief
- Department of Physics and Astronomy, Aarhus University, 8000 Aarhus C, Denmark
| | - K Sishodia
- Quantum Center of Excellence for Diamond and Emergent Materials and Department of Physics, Indian Institute of Technology Madras, Chennai 600036, India
| | - S Mandal
- Indian Institute of Science Education and Research, Pune 411008, India
| | - S De
- Quantum Center of Excellence for Diamond and Emergent Materials and Department of Physics, Indian Institute of Technology Madras, Chennai 600036, India
| | - S R Krishnan
- Quantum Center of Excellence for Diamond and Emergent Materials and Department of Physics, Indian Institute of Technology Madras, Chennai 600036, India
| | - C Medina
- Institute of Physics, University of Freiburg, 79104 Freiburg, Germany
| | - N Pal
- Elettra-Sincrotrone Trieste, 34149 Basovizza, Trieste, Italy
| | - R Richter
- Elettra-Sincrotrone Trieste, 34149 Basovizza, Trieste, Italy
| | - T Fennel
- Institute for Physics, University of Rostock, 18051 Rostock, Germany
| | - M Mudrich
- Department of Physics and Astronomy, Aarhus University, 8000 Aarhus C, Denmark
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6
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Bastian B, Asmussen JD, Ben Ltaief L, Czasch A, Jones NC, Hoffmann SV, Pedersen HB, Mudrich M. A new endstation for extreme-ultraviolet spectroscopy of free clusters and nanodroplets. THE REVIEW OF SCIENTIFIC INSTRUMENTS 2022; 93:075110. [PMID: 35922303 DOI: 10.1063/5.0094430] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Received: 04/03/2022] [Accepted: 06/15/2022] [Indexed: 06/15/2023]
Abstract
In this work, we present a new endstation for the AMOLine of the ASTRID2 synchrotron at Aarhus University, which combines a cluster and nanodroplet beam source with a velocity map imaging and time-of-flight spectrometer for coincidence imaging spectroscopy. Extreme-ultraviolet spectroscopy of free nanoparticles is a powerful tool for studying the photophysics and photochemistry of resonantly excited or ionized nanometer-sized condensed-phase systems. Here, we demonstrate this capability by performing photoelectron-photoion coincidence experiments with pure and doped superfluid helium nanodroplets. Different doping options and beam sources provide a versatile platform to generate various van der Waals clusters as well as He nanodroplets. We present a detailed characterization of the new setup and show examples of its use for measuring high-resolution yield spectra of charged particles, time-of-flight ion mass spectra, anion-cation coincidence spectra, multi-coincidence electron spectra, and angular distributions. A particular focus of the research with this new endstation is on intermolecular charge and energy-transfer processes in heterogeneous nanosystems induced by valence-shell excitation and ionization.
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Affiliation(s)
- Björn Bastian
- Department of Physics and Astronomy, Aarhus University, Ny Munkegade 120, 8000 Aarhus C, Denmark
| | - Jakob D Asmussen
- Department of Physics and Astronomy, Aarhus University, Ny Munkegade 120, 8000 Aarhus C, Denmark
| | - Ltaief Ben Ltaief
- Department of Physics and Astronomy, Aarhus University, Ny Munkegade 120, 8000 Aarhus C, Denmark
| | - Achim Czasch
- Institut für Kernphysik, Goethe Universität, Max-von-Laue-Strasse 1, 60438 Frankfurt, Germany
| | - Nykola C Jones
- Department of Physics and Astronomy, Aarhus University, Ny Munkegade 120, 8000 Aarhus C, Denmark
| | - Søren V Hoffmann
- Department of Physics and Astronomy, Aarhus University, Ny Munkegade 120, 8000 Aarhus C, Denmark
| | - Henrik B Pedersen
- Department of Physics and Astronomy, Aarhus University, Ny Munkegade 120, 8000 Aarhus C, Denmark
| | - Marcel Mudrich
- Department of Physics and Astronomy, Aarhus University, Ny Munkegade 120, 8000 Aarhus C, Denmark
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7
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Asmussen JD, Michiels R, Bangert U, Sisourat N, Binz M, Bruder L, Danailov M, Di Fraia M, Feifel R, Giannessi L, Plekan O, Prince KC, Squibb RJ, Uhl D, Wituschek A, Zangrando M, Callegari C, Stienkemeier F, Mudrich M. Time-Resolved Ultrafast Interatomic Coulombic Decay in Superexcited Sodium-Doped Helium Nanodroplets. J Phys Chem Lett 2022; 13:4470-4478. [PMID: 35561339 DOI: 10.1021/acs.jpclett.2c00645] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 06/15/2023]
Abstract
The autoionization dynamics of superexcited superfluid He nanodroplets doped with Na atoms is studied by extreme-ultraviolet (XUV) time-resolved electron spectroscopy. Following excitation into the higher-lying droplet absorption band, the droplet relaxes into the lowest metastable atomic 1s2s 1,3S states from which interatomic Coulombic decay (ICD) takes place either between two excited He atoms or between an excited He atom and a Na atom attached to the droplet surface. Four main ICD channels are identified, and their decay times are determined by varying the delay between the XUV pulse and a UV pulse that ionizes the initial excited state and thereby quenches ICD. The decay times for the different channels all fall in the range of ∼1 ps, indicating that the ICD dynamics are mainly determined by the droplet environment. A periodic modulation of the transient ICD signals is tentatively attributed to the oscillation of the bubble forming around the localized He excitation.
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Affiliation(s)
- Jakob D Asmussen
- Department of Physics and Astronomy, Aarhus University, 8000 Aarhus C, Denmark
| | - Rupert Michiels
- Institute of Physics, University of Freiburg, 79104 Freiburg im Breisgau, Germany
| | - Ulrich Bangert
- Institute of Physics, University of Freiburg, 79104 Freiburg im Breisgau, Germany
| | - Nicolas Sisourat
- Sorbonne Université, CNRS, Laboratoire de Chimie Physique Matière et Rayonnement, 75005 Paris, France
| | - Marcel Binz
- Institute of Physics, University of Freiburg, 79104 Freiburg im Breisgau, Germany
| | - Lukas Bruder
- Institute of Physics, University of Freiburg, 79104 Freiburg im Breisgau, Germany
| | | | | | - Raimund Feifel
- Department of Physics, University of Gothenburg, 41133 Gothenburg, Sweden
| | - Luca Giannessi
- Elettra-Sincrotrone Trieste S.C.p.A., 34149 Basovizza TS, Italy
| | - Oksana Plekan
- Elettra-Sincrotrone Trieste S.C.p.A., 34149 Basovizza TS, Italy
| | - Kevin C Prince
- Elettra-Sincrotrone Trieste S.C.p.A., 34149 Basovizza TS, Italy
| | - Richard J Squibb
- Department of Physics, University of Gothenburg, 41133 Gothenburg, Sweden
| | - Daniel Uhl
- Institute of Physics, University of Freiburg, 79104 Freiburg im Breisgau, Germany
| | - Andreas Wituschek
- Institute of Physics, University of Freiburg, 79104 Freiburg im Breisgau, Germany
| | - Marco Zangrando
- Elettra-Sincrotrone Trieste S.C.p.A., 34149 Basovizza TS, Italy
| | - Carlo Callegari
- Elettra-Sincrotrone Trieste S.C.p.A., 34149 Basovizza TS, Italy
| | - Frank Stienkemeier
- Institute of Physics, University of Freiburg, 79104 Freiburg im Breisgau, Germany
| | - Marcel Mudrich
- Department of Physics and Astronomy, Aarhus University, 8000 Aarhus C, Denmark
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8
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Briant M, Mestdagh JM, Gaveau MA, Poisson L. Reaction dynamics within a cluster environment. Phys Chem Chem Phys 2022; 24:9807-9835. [PMID: 35441619 DOI: 10.1039/d1cp05783a] [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
This perspective article reviews experimental and theoretical works where rare gas clusters and helium nanodroplets are used as a nanoreactor to investigate chemical dynamics in a solvent environment. A historical perspective is presented first followed by specific considerations on the mobility of reactants within these reaction media. The dynamical response of pure clusters and nanodroplets to photoexcitation is shortly reviewed before examining the role of the cluster (or nanodroplet) degrees of freedom in the photodynamics of the guest atoms and molecules.
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Affiliation(s)
- Marc Briant
- Université Paris-Saclay, CEA, CNRS, LIDYL, 91191, Gif-sur-Yvette, France
| | | | - Marc-André Gaveau
- Université Paris-Saclay, CEA, CNRS, LIDYL, 91191, Gif-sur-Yvette, France
| | - Lionel Poisson
- Université Paris-Saclay, CNRS, Institut des Sciences Moléculaires d'Orsay, 91405, Orsay, France.
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9
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Asmussen JD, Michiels R, Dulitz K, Ngai A, Bangert U, Barranco M, Binz M, Bruder L, Danailov M, Di Fraia M, Eloranta J, Feifel R, Giannessi L, Pi M, Plekan O, Prince KC, Squibb RJ, Uhl D, Wituschek A, Zangrando M, Callegari C, Stienkemeier F, Mudrich M. Unravelling the full relaxation dynamics of superexcited helium nanodroplets. Phys Chem Chem Phys 2021; 23:15138-15149. [PMID: 34259254 DOI: 10.1039/d1cp01041g] [Citation(s) in RCA: 4] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/21/2022]
Abstract
The relaxation dynamics of superexcited superfluid He nanodroplets is thoroughly investigated by means of extreme-ultraviolet (XUV) femtosecond electron and ion spectroscopy complemented by time-dependent density functional theory (TDDFT). Three main paths leading to the emission of electrons and ions are identified: droplet autoionization, pump-probe photoionization, and autoionization induced by re-excitation of droplets relaxing into levels below the droplet ionization threshold. The most abundant product ions are He2+, generated by droplet autoionization and by photoionization of droplet-bound excited He atoms. He+ appear with some pump-probe delay as a result of the ejection He atoms in their lowest excited states from the droplets. The state-resolved time-dependent photoelectron spectra reveal that intermediate excited states of the droplets are populated in the course of the relaxation, terminating in the lowest-lying metastable singlet and triplet He atomic states. The slightly faster relaxation of the triplet state compared to the singlet state is in agreement with the simulation showing faster formation of a bubble around a He atom in the triplet state.
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Affiliation(s)
- Jakob D Asmussen
- Department of Physics and Astronomy, Aarhus University, Denmark.
| | | | - Katrin Dulitz
- Institute of Physics, University of Freiburg, Germany
| | - Aaron Ngai
- Institute of Physics, University of Freiburg, Germany
| | | | - Manuel Barranco
- Departament FQA, Facultat de Física, Universitat de Barcelona, Spain and Institute of Nanoscience and Nanotechnology (IN2UB), Universitat de Barcelona, Spain
| | - Marcel Binz
- Institute of Physics, University of Freiburg, Germany
| | - Lukas Bruder
- Institute of Physics, University of Freiburg, Germany
| | | | | | - Jussi Eloranta
- Department of Chemistry and Biochemistry, California State University at Northridge, Northridge, CA 91330, USA
| | | | - Luca Giannessi
- Institute of Nanoscience and Nanotechnology (IN2UB), Universitat de Barcelona, Spain
| | - Marti Pi
- Departament FQA, Facultat de Física, Universitat de Barcelona, Spain and Institute of Nanoscience and Nanotechnology (IN2UB), Universitat de Barcelona, Spain
| | - Oksana Plekan
- Institute of Nanoscience and Nanotechnology (IN2UB), Universitat de Barcelona, Spain
| | - Kevin C Prince
- Institute of Nanoscience and Nanotechnology (IN2UB), Universitat de Barcelona, Spain
| | | | - Daniel Uhl
- Institute of Physics, University of Freiburg, Germany
| | | | - Marco Zangrando
- Institute of Nanoscience and Nanotechnology (IN2UB), Universitat de Barcelona, Spain and CNR-IOM, Elettra-Sincrotrone Trieste S.C.p.A., Italy
| | - Carlo Callegari
- Institute of Nanoscience and Nanotechnology (IN2UB), Universitat de Barcelona, Spain
| | | | - Marcel Mudrich
- Department of Physics and Astronomy, Aarhus University, Denmark.
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10
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Observation of laser-assisted electron scattering in superfluid helium. Nat Commun 2021; 12:4204. [PMID: 34244517 PMCID: PMC8270992 DOI: 10.1038/s41467-021-24479-w] [Citation(s) in RCA: 5] [Impact Index Per Article: 1.7] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/19/2021] [Accepted: 06/18/2021] [Indexed: 11/08/2022] Open
Abstract
Laser-assisted electron scattering (LAES), a light-matter interaction process that facilitates energy transfer between strong light fields and free electrons, has so far been observed only in gas phase. Here we report on the observation of LAES at condensed phase particle densities, for which we create nano-structured systems consisting of a single atom or molecule surrounded by a superfluid He shell of variable thickness (32-340 Å). We observe that free electrons, generated by femtosecond strong-field ionization of the core particle, can gain several tens of photon energies due to multiple LAES processes within the liquid He shell. Supported by Monte Carlo 3D LAES and elastic scattering simulations, these results provide the first insight into the interplay of LAES energy gain/loss and dissipative electron movement in a liquid. Condensed-phase LAES creates new possibilities for space-time studies of solids and for real-time tracing of free electrons in liquids.
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11
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Mandal S, Gopal R, Shcherbinin M, D'Elia A, Srinivas H, Richter R, Coreno M, Bapat B, Mudrich M, Krishnan SR, Sharma V. Penning spectroscopy and structure of acetylene oligomers in He nanodroplets. Phys Chem Chem Phys 2020; 22:10149-10157. [PMID: 32347252 DOI: 10.1039/d0cp00689k] [Citation(s) in RCA: 7] [Impact Index Per Article: 1.8] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/21/2022]
Abstract
Embedded atoms or molecules in a photoexcited He nanodroplet are well-known to be ionized through inter-atomic relaxation in a Penning process. In this work, we investigate the Penning ionization of acetylene oligomers occurring from the photoexcitation bands of He nanodroplets. In close analogy to conventional Penning electron spectroscopy by thermal atomic collisions, the n = 2 photoexcitation band plays the role of the metastable atomic 1s2s 3,1S He*. This facilitates electron spectroscopy of acetylene aggregates in the sub-Kelvin He environment, providing the following insight into their structure: the molecules in the dopant cluster are loosely bound van der Waals complexes rather than forming covalent compounds. In addition, this work reveals a Penning process stemming from the n = 4 band where charge-transfer from autoionized He in the droplets is known to be the dominant relaxation channel. This allows for excited states of the remnant dopant oligomer Penning-ions to be studied. Hence, we demonstrate Penning ionization electron spectroscopy of doped droplets as an effective technique for investigating dopant oligomers which are easily formed by attachment to the host cluster.
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Affiliation(s)
- S Mandal
- Indian Institute of Science Education and Research, Pune 411008, India
| | - R Gopal
- Tata Institute of Fundamental Research, Hyderabad 500107, India
| | | | - A D'Elia
- Department of Physics, University of Trieste, Via A. Valerio 2, 34127 Trieste, Italy
| | - H Srinivas
- Max-Planck-Institut für Kernphysik, 69117 Heidelberg, Germany
| | - R Richter
- Elettra-Sincrotrone Trieste, 34149 Basovizza, Italy
| | - M Coreno
- Elettra-Sincrotrone Trieste, 34149 Basovizza, Italy and Consiglio Nazionale delle Ricerche - Istituto di Struttura della Materia, 34149 Trieste, Italy
| | - B Bapat
- Indian Institute of Science Education and Research, Pune 411008, India
| | - M Mudrich
- Aarhus University, 8000 Aarhus C, Denmark and Indian Institute of Technology Madras, Chennai 600036, India.
| | - S R Krishnan
- Indian Institute of Technology Madras, Chennai 600036, India.
| | - V Sharma
- Indian Institute of Technology Hyderabad, Kandi 502285, India.
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12
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Ben Ltaief L, Shcherbinin M, Mandal S, Krishnan SR, Richter R, Pfeifer T, Bauer M, Ghosh A, Mudrich M, Gokhberg K, LaForge AC. Electron transfer mediated decay of alkali dimers attached to He nanodroplets. Phys Chem Chem Phys 2020; 22:8557-8564. [DOI: 10.1039/d0cp00256a] [Citation(s) in RCA: 9] [Impact Index Per Article: 2.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/21/2022]
Abstract
Double ionization of alkali dimers attached to He nanodroplets by electron transfer mediated decay (ETMD).
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Affiliation(s)
- L. Ben Ltaief
- Department of Physics and Astronomy
- Aarhus University
- 8000 Aarhus C
- Denmark
| | - M. Shcherbinin
- Department of Physics and Astronomy
- Aarhus University
- 8000 Aarhus C
- Denmark
| | - S. Mandal
- Indian Institute of Science Education and Research
- Pune 411008
- India
| | - S. R. Krishnan
- Indian Institute of Technology Madras
- Chennai 600036
- India
| | - R. Richter
- Elettra-Sincrotrone Trieste
- 34149 Basovizza
- Italy
| | - T. Pfeifer
- Max-Planck-Institut für Kernphysik
- 69117 Heidelberg
- Germany
| | - M. Bauer
- Physikalisch-Chemisches Institut
- Universität Heidelberg
- 69120 Heidelberg
- Germany
| | - A. Ghosh
- Physikalisch-Chemisches Institut
- Universität Heidelberg
- 69120 Heidelberg
- Germany
| | - M. Mudrich
- Department of Physics and Astronomy
- Aarhus University
- 8000 Aarhus C
- Denmark
- Indian Institute of Technology Madras
| | - K. Gokhberg
- Physikalisch-Chemisches Institut
- Universität Heidelberg
- 69120 Heidelberg
- Germany
| | - A. C. LaForge
- Department of Physics
- University of Connecticut
- Storrs
- USA
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13
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Ben Ltaief L, Shcherbinin M, Mandal S, Krishnan SR, LaForge AC, Richter R, Turchini S, Zema N, Pfeifer T, Fasshauer E, Sisourat N, Mudrich M. Charge Exchange Dominates Long-Range Interatomic Coulombic Decay of Excited Metal-Doped Helium Nanodroplets. J Phys Chem Lett 2019; 10:6904-6909. [PMID: 31625747 DOI: 10.1021/acs.jpclett.9b02726] [Citation(s) in RCA: 5] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 06/10/2023]
Abstract
Atoms and molecules attached to rare-gas clusters are ionized by an interatomic autoionization process traditionally termed "Penning ionization" when the host cluster is resonantly excited. Here we analyze this process in the light of the interatomic Coulombic decay (ICD) mechanism, which usually contains a contribution from charge exchange at a short interatomic distance and one from virtual photon transfer at a large interatomic distance. For helium (He) nanodroplets doped with alkali metal atoms (Li, Rb), we show that long-range and short-range contributions to the interatomic autoionization can be clearly distinguished by detecting electrons and ions in coincidence. Surprisingly, ab initio calculations show that even for alkali metal atoms floating in dimples at a large distance from the nanodroplet surface, autoionization is largely dominated by charge-exchange ICD. Furthermore, the measured electron spectra manifest the ultrafast internal relaxation of the droplet mainly into the 1s2s1S state and partially into the metastable 1s2s3S state.
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Affiliation(s)
- L Ben Ltaief
- Department of Physics and Astronomy , Aarhus University , 8000 Aarhus C , Denmark
| | - M Shcherbinin
- Department of Physics and Astronomy , Aarhus University , 8000 Aarhus C , Denmark
| | - S Mandal
- Indian Institute of Science Education and Research , Pune 411008 , India
| | - S R Krishnan
- Department of Physics , Indian Institute of Technology , Madras, Chennai 600 036 , India
| | - A C LaForge
- Department of Physics , University of Connecticut , Storrs , Connecticut 06269 , United States
| | - R Richter
- Elettra-Sincrotrone Trieste , Basovizza, 34149 Trieste , Italy
| | - S Turchini
- Istituto Struttura della Materia-CNR (ISM-CNR) , 00133 Roma , Italy
| | - N Zema
- Istituto Struttura della Materia-CNR (ISM-CNR) , 00133 Roma , Italy
| | - T Pfeifer
- Max-Planck-Institut für Kernphysik , 69117 Heidelberg , Germany
| | - E Fasshauer
- Department of Physics and Astronomy , Aarhus University , 8000 Aarhus C , Denmark
| | - N Sisourat
- Sorbonne Université, CNRS , Laboratoire de Chimie Physique Matière et Rayonnement, UMR 7614 , F-75005 Paris , France
| | - M Mudrich
- Department of Physics and Astronomy , Aarhus University , 8000 Aarhus C , Denmark
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14
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Ionization dynamics of Ne-doped helium clusters at low temperature: Ring-polymer molecular dynamics simulations including electronically nonadiabatic transitions. COMPUT THEOR CHEM 2019. [DOI: 10.1016/j.comptc.2019.112537] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/19/2022]
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15
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Gope K, Luzon I, Strasser D. N-NO & NN-O bond cleavage dynamics in two- and three-body Coulomb explosion of the N 2O 2+ dication. Phys Chem Chem Phys 2019; 21:13730-13737. [PMID: 31206112 DOI: 10.1039/c9cp02908g] [Citation(s) in RCA: 8] [Impact Index Per Article: 1.6] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/21/2022]
Abstract
Triatomic Coulomb explosion dynamics are initiated by single-photon double ionization of N2O with an ultrafast EUV pulse and are probed by delayed near-IR pulses. The triatomic benchmark system exhibits competing two- and three-body dissociation dynamics that are reflected in the time resolved branching ratios and in the co-linear three-body momentum correlation spectra. Both the N-NO and the NN-O bond dissociation channels result in vibrationally excited molecular products. Channel resolved kinetic energy release (KER) spectra exhibit shifts emerging at long probe delays of hundreds of femtoseconds. The asymptotic shifts, towards lower KER indicate that the long-range Coulomb repulsion is effectively screened at bond-distances above ∼16 Å, at which the Rydberg electron is localized on one of the dissociating fragments. Thus, revealing up to a 0.9 eV gap that develops between the molecular Rydberg ion state and its core at long bond distance.
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Affiliation(s)
- Krishnendu Gope
- Institute of Chemistry, Hebrew University of Jerusalem, Jerusalem, Israel.
| | - Itamar Luzon
- Institute of Chemistry, Hebrew University of Jerusalem, Jerusalem, Israel.
| | - Daniel Strasser
- Institute of Chemistry, Hebrew University of Jerusalem, Jerusalem, Israel.
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16
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Shcherbinin M, Westergaard FV, Hanif M, Krishnan SR, LaForge AC, Richter R, Pfeifer T, Mudrich M. Inelastic scattering of photoelectrons from He nanodroplets. J Chem Phys 2019; 150:044304. [PMID: 30709284 DOI: 10.1063/1.5074130] [Citation(s) in RCA: 5] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/24/2022] Open
Abstract
We present a detailed study of inelastic energy-loss collisions of photoelectrons emitted from He nanodroplets by tunable extreme ultraviolet (XUV) radiation. Using coincidence imaging detection of electrons and ions, we probe the lowest He droplet excited states up to the electron impact ionization threshold. We find significant signal contributions from photoelectrons emitted from free He atoms accompanying the He nanodroplet beam. Furthermore, signal contributions from photoionization and electron impact excitation/ionization occurring in pairs of nearest-neighbor atoms in the He droplets are detected. This work highlights the importance of inelastic electron scattering in the interaction of nanoparticles with XUV radiation.
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Affiliation(s)
- M Shcherbinin
- Department of Physics and Astronomy, Aarhus University, 8000 Aarhus C, Denmark
| | - F Vad Westergaard
- Department of Physics and Astronomy, Aarhus University, 8000 Aarhus C, Denmark
| | - M Hanif
- Department of Physics and Astronomy, Aarhus University, 8000 Aarhus C, Denmark
| | - S R Krishnan
- Department of Physics, Indian Institute of Technology, Madras, Chennai 600 036, India
| | - A C LaForge
- Department of Physics, University of Connecticut, Storrs, Connecticut 06269, USA
| | - R Richter
- Elettra-Sincrotrone Trieste, 34149 Basovizza, Trieste, Italy
| | - T Pfeifer
- Max-Planck-Institut für Kernphysik, 69117 Heidelberg, Germany
| | - M Mudrich
- Department of Physics and Astronomy, Aarhus University, 8000 Aarhus C, Denmark
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17
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Thaler B, Ranftl S, Heim P, Cesnik S, Treiber L, Meyer R, Hauser AW, Ernst WE, Koch M. Femtosecond photoexcitation dynamics inside a quantum solvent. Nat Commun 2018; 9:4006. [PMID: 30275442 PMCID: PMC6167364 DOI: 10.1038/s41467-018-06413-9] [Citation(s) in RCA: 25] [Impact Index Per Article: 4.2] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/28/2018] [Accepted: 08/29/2018] [Indexed: 11/13/2022] Open
Abstract
The observation of chemical reactions on the time scale of the motion of electrons and nuclei has been made possible by lasers with ever shortened pulse lengths. Superfluid helium represents a special solvent that permits the synthesis of novel classes of molecules that have eluded dynamical studies so far. However, photoexcitation inside this quantum solvent triggers a pronounced response of the solvation shell, which is not well understood. Here, we present a mechanistic description of the solvent response to photoexcitation of indium (In) dopant atoms inside helium nanodroplets (HeN), obtained from femtosecond pump–probe spectroscopy and time-dependent density functional theory simulations. For the In–HeN system, part of the excited state electronic energy leads to expansion of the solvation shell within 600 fs, initiating a collective shell oscillation with a period of about 30 ps. These coupled electronic and nuclear dynamics will be superimposed on intrinsic photoinduced processes of molecular systems inside helium droplets. Femtosecond laser spectroscopy has contributed to our understanding of structure and function of matter. Here, the authors explore the applicability of superfluid helium nanodroplets as a sample preparation method that allows investigation of previously inaccessible classes of tailor-made or fragile molecular systems.
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Affiliation(s)
- Bernhard Thaler
- Institute of Experimental Physics, Graz University of Technology, Petersgasse 16, 8010, Graz, Austria
| | - Sascha Ranftl
- Institute of Experimental Physics, Graz University of Technology, Petersgasse 16, 8010, Graz, Austria
| | - Pascal Heim
- Institute of Experimental Physics, Graz University of Technology, Petersgasse 16, 8010, Graz, Austria
| | - Stefan Cesnik
- Institute of Experimental Physics, Graz University of Technology, Petersgasse 16, 8010, Graz, Austria
| | - Leonhard Treiber
- Institute of Experimental Physics, Graz University of Technology, Petersgasse 16, 8010, Graz, Austria
| | - Ralf Meyer
- Institute of Experimental Physics, Graz University of Technology, Petersgasse 16, 8010, Graz, Austria
| | - Andreas W Hauser
- Institute of Experimental Physics, Graz University of Technology, Petersgasse 16, 8010, Graz, Austria
| | - Wolfgang E Ernst
- Institute of Experimental Physics, Graz University of Technology, Petersgasse 16, 8010, Graz, Austria
| | - Markus Koch
- Institute of Experimental Physics, Graz University of Technology, Petersgasse 16, 8010, Graz, Austria.
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18
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Shcherbinin M, LaForge AC, Hanif M, Richter R, Mudrich M. Penning Ionization of Acene Molecules by Helium Nanodroplets. J Phys Chem A 2018; 122:1855-1860. [DOI: 10.1021/acs.jpca.7b12506] [Citation(s) in RCA: 13] [Impact Index Per Article: 2.2] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/28/2022]
Affiliation(s)
- M. Shcherbinin
- Department
of Physics and Astronomy, Aarhus University, 8000 Aarhus C, Denmark
| | - A. C. LaForge
- Physikalisches
Institut, Universität Freiburg, 79104 Freiburg, Germany
| | - M. Hanif
- Department
of Physics and Astronomy, Aarhus University, 8000 Aarhus C, Denmark
| | - R. Richter
- Elettra Sincrotrone, 34149 Basovizza, Trieste, Italy
| | - M. Mudrich
- Department
of Physics and Astronomy, Aarhus University, 8000 Aarhus C, Denmark
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19
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Coppens F, von Vangerow J, Barranco M, Halberstadt N, Stienkemeier F, Pi M, Mudrich M. Desorption dynamics of RbHe exciplexes off He nanodroplets induced by spin-relaxation. Phys Chem Chem Phys 2018; 20:9309-9320. [DOI: 10.1039/c8cp00482j] [Citation(s) in RCA: 13] [Impact Index Per Article: 2.2] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/21/2022]
Abstract
Doped He nanodroplets are ideal model systems to study elementary photophysical processes in hetero-nanostructures. Here we study the formation of free RbHe exciplexes from laser-excited Rb-doped He nanodroplets.
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Affiliation(s)
- François Coppens
- Laboratoire des Collisions, Agrégats, Réactivité, IRSAMC, Université Toulouse 3- Paul Sabatier, CNRS UMR 5589
- F-31062 Toulouse Cedex 09
- France
| | | | - Manuel Barranco
- Laboratoire des Collisions, Agrégats, Réactivité, IRSAMC, Université Toulouse 3- Paul Sabatier, CNRS UMR 5589
- F-31062 Toulouse Cedex 09
- France
- Institute of Nanoscience and Nanotechnology (IN2UB), Universitat de Barcelona
- 08028 Barcelona
| | - Nadine Halberstadt
- Laboratoire des Collisions, Agrégats, Réactivité, IRSAMC, Université Toulouse 3- Paul Sabatier, CNRS UMR 5589
- F-31062 Toulouse Cedex 09
- France
| | | | - Martí Pi
- Institute of Nanoscience and Nanotechnology (IN2UB), Universitat de Barcelona
- 08028 Barcelona
- Spain
- Departament FQA, Facultat de Física, Universitat de Barcelona
- 08028 Barcelona
| | - Marcel Mudrich
- Department of Physics and Astronomy, Aarhus University
- Aarhus 8000 C
- Denmark
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20
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Jabbour Al Maalouf E, Neustetter M, Illenberger E, Scheier P, Denifl S. High-Resolution Electron Attachment to the Water Dimer Embedded in Helium Droplets: Direct Observation of the Electronic Conduction Band Formation. J Phys Chem Lett 2017; 8:2220-2223. [PMID: 28467713 PMCID: PMC5439173 DOI: 10.1021/acs.jpclett.7b00691] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.4] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/22/2017] [Accepted: 05/03/2017] [Indexed: 05/29/2023]
Abstract
For bulk liquid helium the bottom of the conduction band (V0) is above the vacuum level. In this case the surface of the liquid represents an electronic surface barrier for an electron to be injected into the liquid. Here we study the electronic conduction band for doped helium droplets of different sizes. Utilizing an electron monochromator, the onset of the (H2O)2- ion yield corresponding to V0 is determined for helium droplets doped with the water dimer. While for larger droplets the onset approaches the well-known bulk value of about 1 eV, the barrier does not continuously decrease with smaller droplet size. A minimum value of V0 = 0.76 ± 0.10 eV is observed, which corresponds to a droplet size of Nmin = 1600 ± 900. For droplet sizes below Nmin, a peak at ∼0 eV appears, which is well-known from neat H2O clusters. Hence, we interpret Nmin as the smallest droplet size in which the electronic band structure is formed in liquid helium droplets.
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Affiliation(s)
- Elias Jabbour Al Maalouf
- Institut
für Ionenphysik und Angewandte Physik, Universität Innsbruck, Technikerstr. 25, A-6020 Innsbruck, Austria
| | - Michael Neustetter
- Institut
für Ionenphysik und Angewandte Physik, Universität Innsbruck, Technikerstr. 25, A-6020 Innsbruck, Austria
| | - Eugen Illenberger
- Institut
für Chemie und Biochemie - Bereich Chemie, Freie Universität Berlin, Takustr. 3, 14195 Berlin, Germany
| | - Paul Scheier
- Institut
für Ionenphysik und Angewandte Physik, Universität Innsbruck, Technikerstr. 25, A-6020 Innsbruck, Austria
| | - Stephan Denifl
- Institut
für Ionenphysik und Angewandte Physik, Universität Innsbruck, Technikerstr. 25, A-6020 Innsbruck, Austria
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21
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Ge Q, Mao Y, White AF, Epifanovsky E, Closser KD, Head-Gordon M. Simulating the absorption spectra of helium clusters (N = 70, 150, 231, 300) using a charge transfer correction to superposition of fragment single excitations. J Chem Phys 2017; 146:044111. [DOI: 10.1063/1.4973611] [Citation(s) in RCA: 11] [Impact Index Per Article: 1.6] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/14/2022] Open
Affiliation(s)
- Qinghui Ge
- Kenneth S. Pitzer Center for Theoretical Chemistry, Department of Chemistry, University of California, Berkeley, California 94720, USA
- Chemical Sciences Division, Lawrence Berkeley National Laboratory, Berkeley, California 94720, USA
| | - Yuezhi Mao
- Kenneth S. Pitzer Center for Theoretical Chemistry, Department of Chemistry, University of California, Berkeley, California 94720, USA
| | - Alec F. White
- Kenneth S. Pitzer Center for Theoretical Chemistry, Department of Chemistry, University of California, Berkeley, California 94720, USA
- Chemical Sciences Division, Lawrence Berkeley National Laboratory, Berkeley, California 94720, USA
| | - Evgeny Epifanovsky
- Q-Chem Inc., 6601 Owens Drive, Suite 105, Pleasanton, California 94588, USA
| | - Kristina D. Closser
- Molecular Foundry, Lawrence Berkeley National Laboratory, Berkeley, California 94720, USA
| | - Martin Head-Gordon
- Kenneth S. Pitzer Center for Theoretical Chemistry, Department of Chemistry, University of California, Berkeley, California 94720, USA
- Chemical Sciences Division, Lawrence Berkeley National Laboratory, Berkeley, California 94720, USA
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22
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LaForge AC, Stumpf V, Gokhberg K, von Vangerow J, Stienkemeier F, Kryzhevoi NV, O'Keeffe P, Ciavardini A, Krishnan SR, Coreno M, Prince KC, Richter R, Moshammer R, Pfeifer T, Cederbaum LS, Mudrich M. Enhanced Ionization of Embedded Clusters by Electron-Transfer-Mediated Decay in Helium Nanodroplets. PHYSICAL REVIEW LETTERS 2016; 116:203001. [PMID: 27258866 DOI: 10.1103/physrevlett.116.203001] [Citation(s) in RCA: 21] [Impact Index Per Article: 2.6] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Received: 12/15/2015] [Indexed: 06/05/2023]
Abstract
We report the observation of electron-transfer-mediated decay (ETMD) involving magnesium (Mg) clusters embedded in helium (He) nanodroplets. ETMD is initiated by the ionization of He followed by removal of two electrons from the Mg clusters of which one is transferred to the He ion while the other electron is emitted into the continuum. The process is shown to be the dominant ionization mechanism for embedded clusters for photon energies above the ionization potential of He. For Mg clusters larger than five atoms we observe stable doubly ionized clusters. Thus, ETMD provides an efficient pathway to the formation of doubly ionized cold species in doped nanodroplets.
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Affiliation(s)
- A C LaForge
- Physikalisches Institut, Universität Freiburg, 79104 Freiburg, Germany
| | - V Stumpf
- Physikalisch-Chemisches Institut, Universität Heidelberg, 69120 Heidelberg, Germany
| | - K Gokhberg
- Physikalisch-Chemisches Institut, Universität Heidelberg, 69120 Heidelberg, Germany
| | - J von Vangerow
- Physikalisches Institut, Universität Freiburg, 79104 Freiburg, Germany
| | - F Stienkemeier
- Physikalisches Institut, Universität Freiburg, 79104 Freiburg, Germany
| | - N V Kryzhevoi
- Physikalisch-Chemisches Institut, Universität Heidelberg, 69120 Heidelberg, Germany
| | - P O'Keeffe
- CNR-Istituto di Struttura della Materia, CP10, 00016 Monterotondo Scalo, Italy
| | - A Ciavardini
- CNR-Istituto di Struttura della Materia, CP10, 00016 Monterotondo Scalo, Italy
| | - S R Krishnan
- Department of Physics, Indian Institute of Technology, Madras, Chennai 600 036, India
| | - M Coreno
- CNR-Istituto di Struttura della Materia, CP10, 00016 Monterotondo Scalo, Italy
| | - K C Prince
- Elettra-Sincrotrone Trieste, Basovizza, Trieste 34149, Italy
| | - R Richter
- Elettra-Sincrotrone Trieste, Basovizza, Trieste 34149, Italy
| | - R Moshammer
- Max-Planck-Institut für Kernphysik, 69117 Heidelberg, Germany
| | - T Pfeifer
- Max-Planck-Institut für Kernphysik, 69117 Heidelberg, Germany
| | - L S Cederbaum
- Physikalisch-Chemisches Institut, Universität Heidelberg, 69120 Heidelberg, Germany
| | - M Mudrich
- Physikalisches Institut, Universität Freiburg, 79104 Freiburg, Germany
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23
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Closser KD, Ge Q, Mao Y, Shao Y, Head-Gordon M. Superposition of Fragment Excitations for Excited States of Large Clusters with Application to Helium Clusters. J Chem Theory Comput 2015; 11:5791-803. [DOI: 10.1021/acs.jctc.5b00703] [Citation(s) in RCA: 14] [Impact Index Per Article: 1.6] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/30/2022]
Affiliation(s)
- Kristina D. Closser
- Kenneth
S. Pitzer Center for Theoretical Chemistry, Department of Chemistry, University of California, Berkeley, California 94720, United States
- Chemical
Sciences Division, Lawrence Berkeley National Laboratory, Berkeley, California 94720, United States
| | - Qinghui Ge
- Kenneth
S. Pitzer Center for Theoretical Chemistry, Department of Chemistry, University of California, Berkeley, California 94720, United States
- Chemical
Sciences Division, Lawrence Berkeley National Laboratory, Berkeley, California 94720, United States
| | - Yuezhi Mao
- Kenneth
S. Pitzer Center for Theoretical Chemistry, Department of Chemistry, University of California, Berkeley, California 94720, United States
| | - Yihan Shao
- Q-Chem, Inc., 6601 Owens
Drive, Suite 105, Pleasanton, California 94588, United States
| | - Martin Head-Gordon
- Kenneth
S. Pitzer Center for Theoretical Chemistry, Department of Chemistry, University of California, Berkeley, California 94720, United States
- Chemical
Sciences Division, Lawrence Berkeley National Laboratory, Berkeley, California 94720, United States
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24
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Observation of correlated electronic decay in expanding clusters triggered by near-infrared fields. Nat Commun 2015; 6:8596. [PMID: 26469997 PMCID: PMC4634218 DOI: 10.1038/ncomms9596] [Citation(s) in RCA: 26] [Impact Index Per Article: 2.9] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/13/2015] [Accepted: 09/09/2015] [Indexed: 11/29/2022] Open
Abstract
When an excited atom is embedded into an environment, novel relaxation pathways can emerge that are absent for isolated atoms. A well-known example is interatomic Coulombic decay, where an excited atom relaxes by transferring its excess energy to another atom in the environment, leading to its ionization. Such processes have been observed in clusters ionized by extreme-ultraviolet and X-ray lasers. Here, we report on a correlated electronic decay process that occurs following nanoplasma formation and Rydberg atom generation in the ionization of clusters by intense, non-resonant infrared laser fields. Relaxation of the Rydberg states and transfer of the available electronic energy to adjacent electrons in Rydberg states or quasifree electrons in the expanding nanoplasma leaves a distinct signature in the electron kinetic energy spectrum. These so far unobserved electron-correlation-driven energy transfer processes may play a significant role in the response of any nano-scale system to intense laser light. In clusters, relaxation of excited atoms can lead to ionization of nearby atoms, a process known as interatomic Coulomb decay. Here, the authors report on a so far unobserved correlated electronic decay process following Rydberg atom generation in clusters ionized by intense near-infrared fields.
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25
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Ziemkiewicz MP, Neumark DM, Gessner O. Ultrafast electronic dynamics in helium nanodroplets. INT REV PHYS CHEM 2015. [DOI: 10.1080/0144235x.2015.1051353] [Citation(s) in RCA: 24] [Impact Index Per Article: 2.7] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/23/2022]
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26
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Ziemkiewicz MP, Bacellar C, Siefermann KR, Leone SR, Neumark DM, Gessner O. Femtosecond time-resolved XUV + UV photoelectron imaging of pure helium nanodroplets. J Chem Phys 2014; 141:174306. [DOI: 10.1063/1.4900503] [Citation(s) in RCA: 13] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/29/2022] Open
Affiliation(s)
- Michael P. Ziemkiewicz
- Ultrafast X-ray Science Laboratory, Chemical Sciences Division, Lawrence Berkeley National Laboratory, Berkeley, California 94720, USA
- Department of Chemistry, University of California, Berkeley, California 94720, USA
| | - Camila Bacellar
- Ultrafast X-ray Science Laboratory, Chemical Sciences Division, Lawrence Berkeley National Laboratory, Berkeley, California 94720, USA
- Department of Chemistry, University of California, Berkeley, California 94720, USA
| | - Katrin R. Siefermann
- Ultrafast X-ray Science Laboratory, Chemical Sciences Division, Lawrence Berkeley National Laboratory, Berkeley, California 94720, USA
- Department of Chemistry, University of California, Berkeley, California 94720, USA
| | - Stephen R. Leone
- Ultrafast X-ray Science Laboratory, Chemical Sciences Division, Lawrence Berkeley National Laboratory, Berkeley, California 94720, USA
- Department of Chemistry, University of California, Berkeley, California 94720, USA
- Department of Physics, University of California, Berkeley, California 94720, USA
| | - Daniel M. Neumark
- Ultrafast X-ray Science Laboratory, Chemical Sciences Division, Lawrence Berkeley National Laboratory, Berkeley, California 94720, USA
- Department of Chemistry, University of California, Berkeley, California 94720, USA
| | - Oliver Gessner
- Ultrafast X-ray Science Laboratory, Chemical Sciences Division, Lawrence Berkeley National Laboratory, Berkeley, California 94720, USA
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27
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28
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Closser KD, Gessner O, Head-Gordon M. Simulations of the dissociation of small helium clusters with ab initio molecular dynamics in electronically excited states. J Chem Phys 2014; 140:134306. [DOI: 10.1063/1.4869193] [Citation(s) in RCA: 27] [Impact Index Per Article: 2.7] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/14/2022] Open
Affiliation(s)
- Kristina D. Closser
- Department of Chemistry, University of California Berkeley, Berkeley, California 94720, USA
- Ultrafast X-Ray Science Laboratory, Chemical Sciences Division, Lawrence Berkeley National Laboratory, Berkeley, California 94720, USA
| | - Oliver Gessner
- Ultrafast X-Ray Science Laboratory, Chemical Sciences Division, Lawrence Berkeley National Laboratory, Berkeley, California 94720, USA
| | - Martin Head-Gordon
- Department of Chemistry, University of California Berkeley, Berkeley, California 94720, USA
- Ultrafast X-Ray Science Laboratory, Chemical Sciences Division, Lawrence Berkeley National Laboratory, Berkeley, California 94720, USA
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29
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Tolbatov I, Bartl P, Yurkovich J, Scheier P, Chipman DM, Denifl S, Ptasinska S. Monocarbon cationic cluster yields from N2/CH4 mixtures embedded in He nanodroplets and their calculated binding energies. J Chem Phys 2014; 140:034316. [PMID: 25669388 DOI: 10.1063/1.4861663] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.2] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/14/2022] Open
Abstract
The formation of monocarbon cluster ions has been investigated by electron ionization mass spectrometry of cold helium nanodroplets doped with nitrogen/methane mixtures. Ion yields for two groups of clusters, CHmN2(+) or CHmN4(+), were determined for mixtures with different molecular ratios of CH4. The possible geometrical structures of these clusters were analyzed using electronic structure computations. Little correlation between the ion yields and the associated binding energies has been observed indicating that in most cases kinetic control is more important than thermodynamic control for forming the clusters.
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Affiliation(s)
- Iogann Tolbatov
- Radiation Laboratory, University of Notre Dame, Notre Dame, Indiana 46556, USA
| | - Peter Bartl
- Institut für Ionenphysik und Angewandte Physik and Center of Molecular Biosciences Innsbruck, Universität Innsbruck, Technikerstraße 25, A-6020 Innsbruck, Austria
| | - James Yurkovich
- Radiation Laboratory, University of Notre Dame, Notre Dame, Indiana 46556, USA
| | - Paul Scheier
- Institut für Ionenphysik und Angewandte Physik and Center of Molecular Biosciences Innsbruck, Universität Innsbruck, Technikerstraße 25, A-6020 Innsbruck, Austria
| | - Daniel M Chipman
- Radiation Laboratory, University of Notre Dame, Notre Dame, Indiana 46556, USA
| | - Stephan Denifl
- Institut für Ionenphysik und Angewandte Physik and Center of Molecular Biosciences Innsbruck, Universität Innsbruck, Technikerstraße 25, A-6020 Innsbruck, Austria
| | - Sylwia Ptasinska
- Radiation Laboratory, University of Notre Dame, Notre Dame, Indiana 46556, USA
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30
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Buchta D, Krishnan SR, Brauer NB, Drabbels M, O’Keeffe P, Devetta M, Di Fraia M, Callegari C, Richter R, Coreno M, Prince KC, Stienkemeier F, Ullrich J, Moshammer R, Mudrich M. Extreme ultraviolet ionization of pure He nanodroplets: Mass-correlated photoelectron imaging, Penning ionization, and electron energy-loss spectra. J Chem Phys 2013; 139:084301. [DOI: 10.1063/1.4818531] [Citation(s) in RCA: 40] [Impact Index Per Article: 3.6] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/14/2022] Open
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31
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Buchta D, Krishnan SR, Brauer NB, Drabbels M, O’Keeffe P, Devetta M, Di Fraia M, Callegari C, Richter R, Coreno M, Prince KC, Stienkemeier F, Moshammer R, Mudrich M. Charge Transfer and Penning Ionization of Dopants in or on Helium Nanodroplets Exposed to EUV Radiation. J Phys Chem A 2013; 117:4394-403. [DOI: 10.1021/jp401424w] [Citation(s) in RCA: 40] [Impact Index Per Article: 3.6] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/30/2022]
Affiliation(s)
- Dominic Buchta
- Physikalisches Institut, Universität Freiburg, 79104 Freiburg, Germany
| | | | - Nils B. Brauer
- Laboratoire de Chimie Physique Moléculaire, Swiss Federal Institute of Technology Lausanne (EPFL), 1015
Lausanne, Switzerland
| | - Marcel Drabbels
- Laboratoire de Chimie Physique Moléculaire, Swiss Federal Institute of Technology Lausanne (EPFL), 1015
Lausanne, Switzerland
| | - Patrick O’Keeffe
- CNR Istituto di Metodologie Inorganiche e dei Plasmi, CP10, 00016 Monterotondo Scalo, Italy
| | - Michele Devetta
- CIMAINA and Dipartimento di Fisica, Università di Milano, 20133 Milano, Italy
| | - Michele Di Fraia
- Department of Physics, University of Trieste, 34128 Trieste, Italy
| | - Carlo Callegari
- Elettra-Sincrotrone Trieste, 34149 Basovizza, Trieste, Italy
| | - Robert Richter
- Elettra-Sincrotrone Trieste, 34149 Basovizza, Trieste, Italy
| | - Marcello Coreno
- CNR Istituto di Metodologie Inorganiche e dei Plasmi, CP10, 00016 Monterotondo Scalo, Italy
| | - Kevin C. Prince
- Elettra-Sincrotrone Trieste, 34149 Basovizza, Trieste, Italy
| | | | | | - Marcel Mudrich
- Physikalisches Institut, Universität Freiburg, 79104 Freiburg, Germany
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32
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Golan A, Ahmed M. Ionization of Water Clusters Mediated by Exciton Energy Transfer from Argon Clusters. J Phys Chem Lett 2012; 3:458-462. [PMID: 26286046 DOI: 10.1021/jz2016654] [Citation(s) in RCA: 30] [Impact Index Per Article: 2.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 06/04/2023]
Abstract
The exciton energy deposited in an argon cluster (Arn, ⟨n = 20⟩) using VUV radiation is transferred to softly ionize doped water clusters ((H2O)n, n = 1-9), leading to the formation of nonfragmented clusters. Following the initial excitation, electronic energy is channeled to ionize the doped water cluster while evaporating the Ar shell, allowing identification of fragmented and complete water cluster ions. Examination of the photoionization efficiency curve shows that cluster evaporation from excitons located above 12.6 eV is not enough to cool the energized water cluster ion and leads to their dissociation to (H2O)n-2H(+) (protonated) clusters.
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Affiliation(s)
- Amir Golan
- Chemical Sciences Division, Lawrence Berkeley National Laboratory, Berkeley, California 94720, United States
| | - Musahid Ahmed
- Chemical Sciences Division, Lawrence Berkeley National Laboratory, Berkeley, California 94720, United States
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33
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Fechner L, Grüner B, Sieg A, Callegari C, Ancilotto F, Stienkemeier F, Mudrich M. Photoionization and imaging spectroscopy of rubidium atoms attached to helium nanodroplets. Phys Chem Chem Phys 2012; 14:3843-51. [PMID: 22327348 DOI: 10.1039/c2cp22749e] [Citation(s) in RCA: 45] [Impact Index Per Article: 3.8] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/21/2022]
Affiliation(s)
- L Fechner
- Physikalisches Institut, Universität Freiburg, Freiburg, Germany
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34
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Kornilov O, Bünermann O, Haxton DJ, Leone SR, Neumark DM, Gessner O. Femtosecond Photoelectron Imaging of Transient Electronic States and Rydberg Atom Emission from Electronically Excited He Droplets. J Phys Chem A 2011; 115:7891-900. [DOI: 10.1021/jp2004216] [Citation(s) in RCA: 33] [Impact Index Per Article: 2.5] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/29/2022]
Affiliation(s)
- Oleg Kornilov
- Ultrafast X-ray Science Laboratory, Chemical Sciences Division, Lawrence Berkeley National Laboratory, Berkeley, California 94720, United States
| | - Oliver Bünermann
- Ultrafast X-ray Science Laboratory, Chemical Sciences Division, Lawrence Berkeley National Laboratory, Berkeley, California 94720, United States
| | - Daniel J. Haxton
- Ultrafast X-ray Science Laboratory, Chemical Sciences Division, Lawrence Berkeley National Laboratory, Berkeley, California 94720, United States
| | - Stephen R. Leone
- Ultrafast X-ray Science Laboratory, Chemical Sciences Division, Lawrence Berkeley National Laboratory, Berkeley, California 94720, United States
| | - Daniel M. Neumark
- Ultrafast X-ray Science Laboratory, Chemical Sciences Division, Lawrence Berkeley National Laboratory, Berkeley, California 94720, United States
| | - Oliver Gessner
- Ultrafast X-ray Science Laboratory, Chemical Sciences Division, Lawrence Berkeley National Laboratory, Berkeley, California 94720, United States
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35
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Closser KD, Head-Gordon M. Ab initio calculations on the electronically excited states of small helium clusters. J Phys Chem A 2010; 114:8023-32. [PMID: 20684573 DOI: 10.1021/jp103532q] [Citation(s) in RCA: 28] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/29/2022]
Abstract
The vertical excitation energies of small helium clusters, He(7) and He(25), have been calculated using configuration interaction singles, and the character of the excited states was determined using attachment/detachment density analysis. It was found that in the n = 2 manifold the excitations could be interpreted as superpositions of atomic states, with excitations on the surface of the clusters being lower in energy than those in the bulk. For the n = 2 excited states with significant density on the interior of the cluster, mixing with the atomic n = 3 states resulted in lower excitation energies. For the n = 3 states the spatial extent of the excited-state density can be much larger than the size of the cluster, making analysis of the states more difficult and highly dependent on the internuclear distance. Introducing disorder into the clusters results in some localization of the excited states, although highly delocalized states are always observed in these small clusters. In addition, experimental results for small clusters are interpreted in terms of these findings.
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Affiliation(s)
- Kristina D Closser
- Department of Chemistry, University of California at Berkeley, and Chemical Sciences Division, Lawrence Berkeley National Laboratory, Berkeley, California 94720, USA
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36
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Kornilov O, Wang CC, Bünermann O, Healy AT, Leonard M, Peng C, Leone SR, Neumark DM, Gessner O. Ultrafast Dynamics in Helium Nanodroplets Probed by Femtosecond Time-Resolved EUV Photoelectron Imaging. J Phys Chem A 2009; 114:1437-45. [DOI: 10.1021/jp907312t] [Citation(s) in RCA: 25] [Impact Index Per Article: 1.7] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/28/2022]
Affiliation(s)
- Oleg Kornilov
- Ultrafast X-ray Science Laboratory, Chemical Sciences Division, Lawrence Berkeley National Laboratory, Berkeley, California 94720, and Department of Chemistry, University of California, Berkeley, California 94720
| | - Chia C. Wang
- Ultrafast X-ray Science Laboratory, Chemical Sciences Division, Lawrence Berkeley National Laboratory, Berkeley, California 94720, and Department of Chemistry, University of California, Berkeley, California 94720
| | - Oliver Bünermann
- Ultrafast X-ray Science Laboratory, Chemical Sciences Division, Lawrence Berkeley National Laboratory, Berkeley, California 94720, and Department of Chemistry, University of California, Berkeley, California 94720
| | - Andrew T. Healy
- Ultrafast X-ray Science Laboratory, Chemical Sciences Division, Lawrence Berkeley National Laboratory, Berkeley, California 94720, and Department of Chemistry, University of California, Berkeley, California 94720
| | - Mathew Leonard
- Ultrafast X-ray Science Laboratory, Chemical Sciences Division, Lawrence Berkeley National Laboratory, Berkeley, California 94720, and Department of Chemistry, University of California, Berkeley, California 94720
| | - Chunte Peng
- Ultrafast X-ray Science Laboratory, Chemical Sciences Division, Lawrence Berkeley National Laboratory, Berkeley, California 94720, and Department of Chemistry, University of California, Berkeley, California 94720
| | - Stephen R. Leone
- Ultrafast X-ray Science Laboratory, Chemical Sciences Division, Lawrence Berkeley National Laboratory, Berkeley, California 94720, and Department of Chemistry, University of California, Berkeley, California 94720
| | - Daniel M. Neumark
- Ultrafast X-ray Science Laboratory, Chemical Sciences Division, Lawrence Berkeley National Laboratory, Berkeley, California 94720, and Department of Chemistry, University of California, Berkeley, California 94720
| | - Oliver Gessner
- Ultrafast X-ray Science Laboratory, Chemical Sciences Division, Lawrence Berkeley National Laboratory, Berkeley, California 94720, and Department of Chemistry, University of California, Berkeley, California 94720
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37
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da Silva FF, Bartl P, Denifl S, Echt O, Märk TD, Scheier P. Argon clusters embedded in helium nanodroplets. Phys Chem Chem Phys 2009; 11:9791-7. [PMID: 19851558 DOI: 10.1039/b913175b] [Citation(s) in RCA: 29] [Impact Index Per Article: 1.9] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/22/2022]
Abstract
Electron impact ionization of argon clusters embedded in helium droplets is investigated. Superior mass resolution makes it possible to distinguish between nominally isobaric cluster ions. An abundance maximum for ArHe(12)(+) is unambiguously confirmed; the spectra also prove the formation of Ar(2)He(n)(+) complexes that had been claimed to fragment into pure Ar(2)(+). Distributions of larger argon cluster ions containing up to 60 atoms closely resemble distributions observed upon electron impact or photoionization of bare argon clusters; caging and evaporative cooling provided by the helium matrix do not suffice to quench fragmentation of the nascent argon cluster ions. Intriguing abundance anomalies are observed in distributions of argon cluster ions that contain water, nitrogen or oxygen impurities. The strong abundance of Ar(55)H(2)O(+), Ar(54)O(2)(+) and Ar(54)N(2)(+) contrasts with the virtual absence of slightly larger cluster ions containing the corresponding impurities. The features are probably related to enhanced cluster ion stability upon closure of the second icosahedral shell but the difference in magic numbers (54 versus 55) and the well-known reactivity of charged argon-nitrogen complexes suggest structural differences.
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Affiliation(s)
- Filipe Ferreira da Silva
- Institut für Ionenphysik und Angewandte Physik, Leopold Franzens Universität, Technikerstr. 25, A-6020 Innsbruck, Austria
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