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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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2
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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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3
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Otani H, Nakahara H, Goto H, Kuma S, Momose T. Electronic spectroscopy of Mg-phthalocyanine embedded in cold hydrogen clusters produced by a pulsed nozzle. J Chem Phys 2021; 155:044309. [PMID: 34340371 DOI: 10.1063/5.0056499] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/14/2022] Open
Abstract
Cold clusters of molecular hydrogen were created using a pulsed nozzle. The thermodynamical states of the clusters were characterized by measuring the cluster beam velocity and the laser-induced fluorescence (LIF) spectra of embedded molecules. Two distinct velocity components were identified in the beam that originates from different clustering mechanisms. The fast velocity component corresponds to the expansion of H2 from the gas phase, while the slow velocity component corresponds to the expansion from the liquid phase. The velocity distribution of these two components showed no significant difference between the expansions of para and normal hydrogen. In this study, LIF spectroscopy of single Mg-phthalocyanine molecules embedded in the H2 clusters consisting of 105 H2 molecules was used to investigate the properties of the fast component. The observed peak frequencies of the LIF signals, compared to those observed in helium droplets, were used to infer the possible presence of the liquid phase in the fast component of the H2 clusters below 5 K. The shift, linewidth, and splitting in the spectra, which strongly depend on the ortho/para ratio, are attributed to the local configurations of hydrogen in the vicinity of the probe molecules.
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Affiliation(s)
- Hatsuki Otani
- Department of Chemistry, The University of British Columbia, Vancouver, British Columbia V6T 1Z1, Canada
| | - Hiroko Nakahara
- Department of Chemistry, The University of British Columbia, Vancouver, British Columbia V6T 1Z1, Canada
| | - Haruka Goto
- Division of Chemistry, Graduate School of Science, Kyoto University, Kyoto 606-8502, Japan
| | - Susumu Kuma
- Atomic, Molecular, and Optical Physics Laboratory, RIKEN, Saitama 351-0198, Japan
| | - Takamasa Momose
- Department of Chemistry, The University of British Columbia, Vancouver, British Columbia V6T 1Z1, Canada
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4
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Hoshina H, Sliter R, Ravi A, Kuma S, Momose T, Vilesov AF. Ro‐vibrational Spectra of (
para
‐H
2
)
N
‐CH
4
in He Droplets. Chemphyschem 2016; 17:3818-3825. [DOI: 10.1002/cphc.201600484] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.1] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/10/2016] [Indexed: 11/10/2022]
Affiliation(s)
- Hiromichi Hoshina
- Department of Chemistry University of Southern California Los Angeles CA 90089 USA
- Terahertz Sensing and Imaging Laboratory RIKEN 519-1399 Aramaki-Aoba, Aoba-ku Sendai, Miyagi 980-0845 Japan
| | - Russell Sliter
- Department of Chemistry University of Southern California Los Angeles CA 90089 USA
- KLA-Tencor 1 Technology Drive Milpitas CA 95035 USA
| | - Aakash Ravi
- Department of Chemistry The University of British Columbia Vancouver BC V6T 1Z1 Canada
- Department of Physics Harvard University 17 Oxford Street Cambridge MA 02138 USA
| | - Susumu Kuma
- Department of Chemistry The University of British Columbia Vancouver BC V6T 1Z1 Canada
- Atomic, Molecular & Optical Physics Laboratory RIKEN 2-1 Hirosawa Wako Saitama 351-0198 Japan
| | - Takamasa Momose
- Department of Chemistry The University of British Columbia Vancouver BC V6T 1Z1 Canada
| | - Andrey F. Vilesov
- Department of Chemistry University of Southern California Los Angeles CA 90089 USA
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5
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Dvorak M, Müller M, Bünermann O, Stienkemeier F. Size dependent transition to solid hydrogen and argon clusters probed via spectroscopy of PTCDA embedded in helium nanodroplets. J Chem Phys 2015; 140:144301. [PMID: 24735293 DOI: 10.1063/1.4870395] [Citation(s) in RCA: 8] [Impact Index Per Article: 0.9] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/27/2022] Open
Abstract
Complexes made of either Ar(N) or (H2)N clusters (N = 1-170) and a single PTCDA molecule (3,4,9,10-perylene-tetracarboxylic-dianhydride) are assembled inside helium droplets and spectroscopically studied via laser-induced fluorescence spectroscopy. The frequency shift and line-broadening are analyzed as a function of N and of the pick-up order of the PTCDA and cluster material in order to track liquid or solid properties of the clusters. For argon, the solid phase is observed for N > 10 above which the pick-up order dramatically influences the localization of the chromophore with respect to the Ar cluster. If the droplets are doped first with Ar, the chromophore remains on the surface of a solid cluster whereas for the reversed pick-up order the molecule is surrounded by an argon shell. At N < 10 wetting and the formation of the first solvation shell are observed. For para-hydrogen, a transition to the solid is observed at N ~ 20-25, confirming previous theoretical predictions on the existence of a liquid-like phase at such small sizes, even below the bulk hydrogen freezing temperature.
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Affiliation(s)
- Matthieu Dvorak
- Physikalisches Institut, Universität Freiburg, Hermann-Herder-Str. 3, 79104 Freiburg, Germany
| | - Markus Müller
- Physikalisches Institut, Universität Freiburg, Hermann-Herder-Str. 3, 79104 Freiburg, Germany
| | - Oliver Bünermann
- Institut für Physikalische Chemie, Georg-August-Universität Tammannstr. 6, 37077 Göttingen, Germany
| | - Frank Stienkemeier
- Physikalisches Institut, Universität Freiburg, Hermann-Herder-Str. 3, 79104 Freiburg, Germany
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Hayashi M, Ohshima Y. Sub-Doppler Electronic Spectra of Benzene–(H2)n Complexes. J Phys Chem A 2013; 117:9819-30. [DOI: 10.1021/jp312754v] [Citation(s) in RCA: 4] [Impact Index Per Article: 0.4] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/28/2022]
Affiliation(s)
- Masato Hayashi
- Institute
for Molecular Science, National Institutes of Natural Sciences, Myodaiji,
Okazaki 444-8585, Japan
| | - Yasuhiro Ohshima
- Institute
for Molecular Science, National Institutes of Natural Sciences, Myodaiji,
Okazaki 444-8585, Japan
- SOKENDAI, The Graduate University for Advanced Studies, Okazaki 444-8585, Japan
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7
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8
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Dvorak M, Müller M, Knoblauch T, Bünermann O, Rydlo A, Minniberger S, Harbich W, Stienkemeier F. Spectroscopy of 3, 4, 9, 10-perylenetetracarboxylic dianhydride (PTCDA) attached to rare gas samples: Clusters vs. bulk matrices. I. Absorption spectroscopy. J Chem Phys 2012; 137:164301. [DOI: 10.1063/1.4759443] [Citation(s) in RCA: 16] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/14/2022] Open
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9
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Benedek G, Hizhnyakov V. Fermi sea excitations in the optical spectrum of a doped 3He droplet. Chem Phys Lett 2012. [DOI: 10.1016/j.cplett.2012.07.065] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.1] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/28/2022]
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10
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Hizhnyakov V. Zero-phonon lines of systems with different dimensions and unconventional vibronic interactions. JOURNAL OF PHYSICS. CONDENSED MATTER : AN INSTITUTE OF PHYSICS JOURNAL 2012; 24:104011. [PMID: 22353367 DOI: 10.1088/0953-8984/24/10/104011] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.1] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 05/31/2023]
Abstract
The standard theory of the optical spectra of impurity centres in solids predicts the Lorentzian shape of the zero-phonon lines to have temperature-dependent position and width. However, in recent years different systems, including ones of reduced dimension, have been found, in which remarkable deviations from the standard laws have been observed. Generalizations of the theory to these systems are presented. Among other things, the quantum liquid 3He doped by optical centres is considered.
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Affiliation(s)
- V Hizhnyakov
- Institute of Physics, University of Tartu, Tartu, Estonia.
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11
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Krishnan SR, Fechner L, Kremer M, Sharma V, Fischer B, Camus N, Jha J, Krishnamurthy M, Pfeifer T, Moshammer R, Ullrich J, Stienkemeier F, Mudrich M, Mikaberidze A, Saalmann U, Rost JM. Dopant-induced ignition of helium nanodroplets in intense few-cycle laser pulses. PHYSICAL REVIEW LETTERS 2011; 107:173402. [PMID: 22107516 DOI: 10.1103/physrevlett.107.173402] [Citation(s) in RCA: 11] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Received: 07/22/2011] [Indexed: 05/31/2023]
Abstract
We demonstrate ultrafast resonant energy absorption of rare-gas doped He nanodroplets from intense few-cycle (~10 fs) laser pulses. We find that less than 10 dopant atoms "ignite" the droplet to generate a nonspherical electronic nanoplasma resulting ultimately in complete ionization and disintegration of all atoms, although the pristine He droplet is transparent for the laser intensities applied. Our calculations at those intensities reveal that the minimal pulse length required for ignition is about 9 fs.
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Affiliation(s)
- S R Krishnan
- Max-Planck-Institut für Kernphysik, Saupfercheckweg 1, 69117 Heidelberg, Germany
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12
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Whitley HD, DuBois JL, Whaley KB. Theoretical Analysis of the Anomalous Spectral Splitting of Tetracene in 4He Droplets. J Phys Chem A 2011; 115:7220-33. [DOI: 10.1021/jp2003003] [Citation(s) in RCA: 17] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/28/2022]
Affiliation(s)
- Heather D. Whitley
- Department of Chemistry and Kenneth S. Pitzer Center for Theoretical Chemistry, University of California, Berkeley, California 94720, United States
- Lawrence Livermore National Laboratory, PO Box 808, Livermore, California 94550, United States
| | - Jonathan L. DuBois
- Department of Chemistry and Kenneth S. Pitzer Center for Theoretical Chemistry, University of California, Berkeley, California 94720, United States
- Lawrence Livermore National Laboratory, PO Box 808, Livermore, California 94550, United States
| | - K. Birgitta Whaley
- Department of Chemistry and Kenneth S. Pitzer Center for Theoretical Chemistry, University of California, Berkeley, California 94720, United States
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13
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Kuma S, Nakahara H, Tsubouchi M, Takahashi A, Mustafa M, Sim G, Momose T, Vilesov AF. Laser Induced Fluorescence Spectroscopy of Tetracene with Large Ar, Ne, and H2 Clusters in Superfluid He Nanodroplets. J Phys Chem A 2011; 115:7392-9. [DOI: 10.1021/jp203341r] [Citation(s) in RCA: 13] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/28/2022]
Affiliation(s)
- Susumu Kuma
- Department of Chemistry, The University of British Columbia, Vancouver, BC V6T 1Z1, Canada
| | - Hiroko Nakahara
- Department of Physics and Astronomy, The University of British Columbia, Vancouver, BC V6T 1Z1, Canada
| | - Masaaki Tsubouchi
- Department of Chemistry, The University of British Columbia, Vancouver, BC V6T 1Z1, Canada
| | - Akira Takahashi
- Department of Chemistry, The University of British Columbia, Vancouver, BC V6T 1Z1, Canada
| | - Majd Mustafa
- Department of Chemistry, The University of British Columbia, Vancouver, BC V6T 1Z1, Canada
| | - Goeun Sim
- Department of Chemistry, The University of British Columbia, Vancouver, BC V6T 1Z1, Canada
| | - Takamasa Momose
- Department of Chemistry, The University of British Columbia, Vancouver, BC V6T 1Z1, Canada
- Department of Physics and Astronomy, The University of British Columbia, Vancouver, BC V6T 1Z1, Canada
| | - Andrey F. Vilesov
- Department of Chemistry, University of Southern California, Los Angeles, California 90089, United States
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14
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Cargnoni F, Mella M. Solubility of Metal Atoms in Helium Droplets: Exploring the Effect of the Well Depth Using the Coinage Metals Cu and Ag. J Phys Chem A 2011; 115:7141-52. [PMID: 21425774 DOI: 10.1021/jp112408d] [Citation(s) in RCA: 19] [Impact Index Per Article: 1.5] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/28/2022]
Affiliation(s)
| | - Massimo Mella
- School of Chemistry, Cardiff University, Main Building, CF10 3AT Cardiff, United Kingdom
- Dipartimento di Scienze Chimiche ed Ambientali, Università degli Studi dell’Insubria, via Lucini 3, 22100 Como (I), Italy
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15
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Whitley HD, DuBois JL, Whaley KB. Spectral shifts and helium configurations in 4He(N)-tetracene clusters. J Chem Phys 2009; 131:124514. [PMID: 19791901 DOI: 10.1063/1.3236386] [Citation(s) in RCA: 23] [Impact Index Per Article: 1.5] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/15/2022] Open
Abstract
Spectral shifts of electronic transitions of tetracene in helium droplets are investigated in a theoretical study of (4)He(N)-tetracene clusters with 1 < or = N < or = 150. Utilizing a pairwise interaction for the S(0) state of tetracene with helium that is extended by semiempirical terms to construct a potential for the S(1) state of tetracene with helium, the spectral shift is calculated from path integral Monte Carlo calculations of the helium equilibrium properties with tetracene in the S(0) and S(1) states at T = 0 and at T = 0.625 K. The calculated spectral shifts are in quantitative agreement with available experimental measurements for small values of N (< or = 8) at T approximately 0.4 K and show qualitative agreement for larger N (10-20). The extrapolated value of the spectral shift in large droplets (N approximately 10(4)) is approximately 90% of the experimentally measured value. We find no evidence of multiple configurations of helium for any cluster size for either the S(0) or S(1) state of tetracene. These results suggest that the observed spectral splitting of electronic transitions of tetracene in large helium droplets is not due to the coexistence of static metastable helium densities, unlike the situation previously analyzed for the phthalocyanine molecule.
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Affiliation(s)
- Heather D Whitley
- Department of Chemistry and Kenneth S. Pitzer Center for Theoretical Chemistry, University of California, Berkeley, California 94720, USA.
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16
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Jaksch S, Mauracher A, Bacher A, Denifl S, da Silva FF, Schöbel H, Echt O, Märk TD, Probst M, Bohme DK, Scheier P. Formation of even-numbered hydrogen cluster cations in ultracold helium droplets. J Chem Phys 2009; 129:224306. [PMID: 19071915 DOI: 10.1063/1.3035833] [Citation(s) in RCA: 27] [Impact Index Per Article: 1.8] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/15/2022] Open
Abstract
Neutral hydrogen clusters are grown in ultracold helium nanodroplets by successive pickup of hydrogen molecules. Even-numbered hydrogen cluster cations are observed upon electron-impact ionization with and without attached helium atoms and in addition to the familiar odd-numbered H(n)(+). The helium matrix affects the fragmentation dynamics that usually lead to the formation of overwhelmingly odd-numbered H(n)(+). The use of high-resolution mass spectrometry allows the unambiguous identification of even-numbered H(n)(+) up to n approximately = 120 by their mass excess that distinguishes them from He(n)(+), mixed He(m)H(n)(+), and background ions. The large range in size of these hydrogen cluster ions is unprecedented, as is the accuracy of their definition. Apart from the previously observed magic number n=6, pronounced drops in the abundance of even-numbered cluster ions are seen at n=30 and 114, which suggest icosahedral shell closures at H(6)(+)(H(2))(12) and H(6)(+)(H(2))(54). Possible isomers of H(6)(+) are identified at the quadratic configuration interaction with inclusion of single and double excitations (QCISD)/aug-cc-pVTZ level of theory.
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Affiliation(s)
- S Jaksch
- Institut für Ionenphysik und Angewandte Physik, Leopold Franzens Universität, Technikerstr. 25, A-6020 Innsbruck, Austria
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17
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Kuyanov-Prozument K, Vilesov AF. Hydrogen clusters that remain fluid at low temperature. PHYSICAL REVIEW LETTERS 2008; 101:205301. [PMID: 19113350 DOI: 10.1103/physrevlett.101.205301] [Citation(s) in RCA: 16] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Received: 03/07/2008] [Revised: 07/03/2008] [Indexed: 05/27/2023]
Abstract
Superfluidity of hydrogen, predicted three decades ago, continues to elude experimental observation, due to the high freezing temperature of H2 at T=13.8 K. Here, large para-H2 clusters are obtained in a cryogenic pulsed free jet expansion and are studied via nonlinear Raman spectroscopy. Clusters formed from neat pH_{2} are solid as evidenced by the characteristic splitting of the rotational S0(0) line. However, clusters formed of highly diluted pH_{2} (< or = 1%) in He have a single S0(0) line and remain liquid at the estimated superfluid transition temperature of T=1-2 K.
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18
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Slipchenko MN, Sartakov BG, Vilesov AF. Evolution of the vibrational spectrum of ammonia from single molecule to bulk. J Chem Phys 2008; 128:134509. [DOI: 10.1063/1.2884927] [Citation(s) in RCA: 46] [Impact Index Per Article: 2.9] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/29/2022] Open
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