Library

X
feed icon rss

Your email was sent successfully. Check your inbox.

An error occurred while sending the email. Please try again.

Proceed reservation?

Export
  • 1
    Electronic Resource
    Electronic Resource
    Critical appearance size of doubly charged Xe clusters revisited (1989)
    College Park, Md. : American Institute of Physics (AIP)
    The Journal of Chemical Physics 90 (1989), S. 4091-4094 
    Details
    ISSN: 1089-7690
    Source: AIP Digital Archive
    Topics: Physics , Chemistry and Pharmacology
    Notes: In previous experiments on doubly charged Xe clusters, no Xe2+n cluster ions were observed for n less than 53 atoms and no Xe3+n for n less than 114 atoms. From recent computer simulations it was inferred that Xe2+51 ions have lifetimes ∼100 ps while Xe2+55 ions have lifetimes ∼10 μs in agreement with these previous experimental results. Using a high performance mass spectrometer we have repeated these experiments. In contrast to these earlier findings, we are here able to observe doubly charged Xe cluster ions with sizes down to n2=47 (at lifetimes of ∼400 μs). The critical appearance size for triply charged Xe clusters is n3=108. In accordance with a recently suggested sequential ionization mechanism for the production of stable doubly charged van der Waals cluster ions, the appearance energy of Xe2+n was found to lie well below the appearance energy of Xe2+ from Xe.
    Type of Medium: Electronic Resource
    URL: http://dx.doi.org/10.1063/1.455766
    Library Location Call Number Volume/Issue/Year Availability
    BibTip Others were also interested in ...
    Paper (German National Licenses)
    Fulltext
  • 2
    Electronic Resource
    Electronic Resource
    Dissociative electron attachment to CF2Cl2 (1999)
    Springer
    Czechoslovak journal of physics 49 (1999), S. 383-392 
    Details
    ISSN: 1572-9486
    Source: Springer Online Journal Archives 1860-2000
    Topics: Physics
    Notes: Abstract Using a recently constructed high resolution crossed electron/molecular beam apparatus consisting of a hemispherical electron monochromator and a quadrupole mass spectrometer we have measured the relative production cross sections for CI– and F– via electron attachment to CF2Cl2. The relative Cl– cross section is placed on an absolute scale by reference to an absolute rate coefficient using a calibration method involving integration of the measured anion signal. The most efficient Cl– production process is at about zero energy and its magnitude is resolution limited. The present high resolution value of 6 × 10−16 cm2 compares well with an earlier value reported by Chen and Chantry. A second peak is detected at around 0.8 eV in accordance with some of the earlier beam and swarm measurements. The observed production of F– has an appearance energy of 1.9 eV and the energy of maximum cross section is 3.36 eV, the latter value comparing well with several previous studies.
    Type of Medium: Electronic Resource
    URL: http://dx.doi.org/10.1023/A:1022857202672
    Library Location Call Number Volume/Issue/Year Availability
    BibTip Others were also interested in ...
    Paper (German National Licenses)
    Fulltext
  • 3
    Electronic Resource
    Electronic Resource
    Dissociative electron attachment to CO2 (1998)
    Springer
    Czechoslovak journal of physics 48 (1998), S. 1135-1145 
    Details
    ISSN: 1572-9486
    Source: Springer Online Journal Archives 1860-2000
    Topics: Physics
    Notes: Abstract The 4.4eV dissociative electron attachment peak in CO2 was reinvestigated paying particular attention to (i) its structure associated with vibrational excitation and to (ii) the temperature dependence of the onset. For this purpose we have used two specially designed crossed beams machines, one having a trochoidal electron analyzer (TEM) and one with a hemispherical electron analyzer (HEM) for the production of the highly monochromatized electron beams (with FWHM's down to 5 and 50meV, respectively). The present results confirm the earlier findings in (i) interpreting the dominant structures of the 4.4eV peak as being due to vibrationally excited states of CO in the reaction CO2 + e → O-+ CO and (ii) assigning the much weaker and narrower structures to the intermediate CO 2 - . In the temperature range between 300 and 245 K almost no temperature dependence of the onset can be seen in the present study. In comparison to NO and CO where the onset is vertical the CO2 threshold behavior is less steep indicating that in the CO2 case a different type of transition must be responsible for the onset of the O− production. Besides DA to CO2 we have for comparison and calibration purposes investigated also DA to CO and NO.
    Type of Medium: Electronic Resource
    URL: http://dx.doi.org/10.1023/A:1022849832444
    Library Location Call Number Volume/Issue/Year Availability
    BibTip Others were also interested in ...
    Paper (German National Licenses)
    Fulltext
  • 4
    Electronic Resource
    Electronic Resource
    Unimolecular dissociation of singly- and multiply-charged fullerene ions (1997)
    Springer
    Hyperfine interactions 108 (1997), S. 95-105 
    Details
    ISSN: 1572-9540
    Source: Springer Online Journal Archives 1860-2000
    Topics: Physics
    Notes: Abstract The formation of fragment ions from C60 due to electron impact ionization leading to a bimodal fragmentation pattern with a minimum around the cluster size of 30 is investigated with help of mass spectrometric techniques. Based on a detailed analysis of the energetics and kinetics of the singly- and multiply-charged fragment ions by two-sector field mass spectrometry (MIKE-scans) we can conclude that on the one hand some of the dissociation reactions proceed via evaporation of an intact C6 + or C4 + unit (and not via the sequential loss of smaller molecular carbon units). On the other hand, measured appearance energies and the direct observation of sequential C2-loss reactions confirm that the sequential loss of neutral C2 units is the dominant production mechanism for Cn z+ fragment ions with sizes 40 〈 n 〈 60.
    Type of Medium: Electronic Resource
    URL: http://dx.doi.org/10.1023/A:1012681906450
    Library Location Call Number Volume/Issue/Year Availability
    BibTip Others were also interested in ...
    Paper (German National Licenses)
    Fulltext
  • 5
    Electronic Resource
    Electronic Resource
    Stability of multiply charged fullerene ions (1999)
    Springer
    The European physical journal 9 (1999), S. 91-94 
    Details
    ISSN: 1434-6079
    Keywords: PACS: 36.40.Qv Stability and fragmentation of clusters – 81.05.Tp Fullerenes and related materials; diamonds, graphite
    Source: Springer Online Journal Archives 1860-2000
    Topics: Physics
    Notes: Abstract. Spontaneous (metastable) and surface-induced decay reactions for multiply charged fullerene ions, investigated recently in Innsbruck, are reviewed. Results discussed include the mechanisms and energetics of C2 evaporation and charge separation reactions, the secondary electron emission upon impact on gold surfaces, and surface-induced reactions of singly and multiply charged fullerene ions.
    Type of Medium: Electronic Resource
    URL: http://dx.doi.org/10.1007/s100530050405
    Library Location Call Number Volume/Issue/Year Availability
    BibTip Others were also interested in ...
    Paper (German National Licenses)
    Fulltext
  • 6
    Electronic Resource
    Electronic Resource
    Low energy acetone dimer ion/surface collisions studied with high energy resolution (1999)
    Springer
    The European physical journal 9 (1999), S. 551-556 
    Details
    ISSN: 1434-6079
    Keywords: PACS: 34.90.+q Other topics in atomic and molecular collision processes and interactions – 82.65.Fr Film and membrane processes: ion exchange, dialyse, osmosis, electroosmosis – 82.30.Fi Ion–molecule, ion–ion, and charge transfer reactions
    Source: Springer Online Journal Archives 1860-2000
    Topics: Physics
    Notes: Abstract. We have recently constructed the tandem mass spectrometer set-up BESTOF (consisting of a B-sector field combined with an E-sector field, a Surface and a Time Of Flight mass spectrometer) which allows the investigation of ion/surface reactions with high primary mass and energy resolution. Using BESTOF we have extended previous investigations from molecular projectile ions to cluster ions. In particular, we have studied here surface induced dissociation (SID) and surface induced reactions (SIR) of acetone dimer ions upon impact on a hydrocarbon covered stainless steel surface as a function of incident collision energy up to about 80 eV.
    Type of Medium: Electronic Resource
    URL: http://dx.doi.org/10.1007/PL00010954
    Library Location Call Number Volume/Issue/Year Availability
    BibTip Others were also interested in ...
    Paper (German National Licenses)
    Fulltext
  • 7
    Electronic Resource
    Electronic Resource
    Electron attachment to nitric oxide clusters and electron impact ionization of carbon monoxide clusters (1999)
    Springer
    The European physical journal 9 (1999), S. 159-162 
    Details
    ISSN: 1434-6079
    Keywords: PACS: 36.40.-c Atomic and molecular clusters – 34.80.Lx Electron–ion recombination and electron attachment
    Source: Springer Online Journal Archives 1860-2000
    Topics: Physics
    Notes: Abstract. The formation of both positively and negatively charged ions after interaction of electrons with different cluster beams is investigated, by the use of highly monochomatized electron beams. In the case of the electron attachment to neutral NO clusters, the formation of the monomer ion NO- could be observed for the first time. The only explanation for the creation of such an ion is an intracluster reaction. In the case of carbon monoxide clusters, the appearance energies were determined with high accuracy. From these data, we derived the binding energy of the cluster dimer. Our results are in good agreement with photoionization studies.
    Type of Medium: Electronic Resource
    URL: http://dx.doi.org/10.1007/PL00010924
    Library Location Call Number Volume/Issue/Year Availability
    BibTip Others were also interested in ...
    Paper (German National Licenses)
    Fulltext
  • 8
    Electronic Resource
    Electronic Resource
    Universal behaviour in fragmentation phenomena? The cluster case (1999)
    Springer
    The European physical journal 5 (1999), S. 5-8 
    Details
    ISSN: 1434-6079
    Keywords: PACS. 36.40.Ei Phase transitions in clusters - 05.70.Fh Phase transitions: general aspects - 36.40.Qv Stability and fragmentation of clusters
    Source: Springer Online Journal Archives 1860-2000
    Topics: Physics
    Notes: Abstract: We report the first account of a cluster fragmentation study involving high energy cluster-cluster collisions in which all the fragments of each collision occurring in the experiment are mass analyzed on an event by event basis. This allows an unbiased look at the true nature of fragmentation including a statistical analysis in terms of fluctuations in the fragment size distribution.
    Type of Medium: Electronic Resource
    URL: http://dx.doi.org/10.1007/s100530050222
    Library Location Call Number Volume/Issue/Year Availability
    BibTip Others were also interested in ...
    Paper (German National Licenses)
    Fulltext
  • 9
    Electronic Resource
    Electronic Resource
    Calculation of absolute electron-impact ionization cross-sections of dimers and trimers (2000)
    Springer
    The European physical journal 12 (2000), S. 283-287 
    Details
    ISSN: 1434-6079
    Keywords: PACS. 34.50.Gb Electronics excitation and ionization of molecules; intermediate molecular states (including lifetimes, state mixing, etc.) – 34.80.Dp Atomic excitation and ionization by electron impact
    Source: Springer Online Journal Archives 1860-2000
    Topics: Physics
    Notes: Abstract: We report calculations of the electron-impact ionization cross-sections of selected dimers (homonuclear diatomic molecules) and trimers (homonuclear triatomic molecules) using a method which relies only on macroscopic quantities in conjunction with a “defect concept”. The empirically determined defect describes the deviation of the cluster (dimer, trimer) cross-sections from a simple linear dependence on the cluster size. We compare the calculated cross-sections to experimental data for the dimers S2 and F2 and the trimer O3 and we present predictions for the ionization cross-sections of Br2, I2, C2 and C3 for which no experimental data are available. Lastly, we extend the method to the calculation of ionization cross-sections for the fullerenes C60 and C70.
    Type of Medium: Electronic Resource
    URL: http://dx.doi.org/10.1007/s100530070023
    Library Location Call Number Volume/Issue/Year Availability
    BibTip Others were also interested in ...
    Paper (German National Licenses)
    Fulltext
Close ⊗
This website uses cookies and the analysis tool Matomo. More information can be found here...