ALBERT

All Library Books, journals and Electronic Records Telegrafenberg

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
    College Park, Md. : American Institute of Physics (AIP)
    The Journal of Chemical Physics 97 (1992), S. 5177-5181 
    ISSN: 1089-7690
    Source: AIP Digital Archive
    Topics: Physics , Chemistry and Pharmacology
    Notes: Recent experiments on the H/Ni(111) system have demonstrated that high-resolution electron-energy-loss spectra of subsurface absorbate species can be observed. We report here molecular-dynamics simulations for both the H/Ni(111) and H/Pd(111) systems. The necessary atomic forces are obtained from embedded atom method (EAM) potentials. From such calculations we have obtained the power spectra and compare our results to the available experimental data. These calculations reasonably reproduce the observed shifts upon embedding the H subsurface and we comment on the possibility of subsurface absorbates interfering with surface adsorbate assignments. Lastly, we illustrate the sensitivity of our results to the parametrization of the EAM potential.
    Type of Medium: Electronic Resource
    Location Call Number Expected Availability
    BibTip Others were also interested in ...
  • 2
    Electronic Resource
    Electronic Resource
    College Park, Md. : American Institute of Physics (AIP)
    The Journal of Chemical Physics 95 (1991), S. 3506-3520 
    ISSN: 1089-7690
    Source: AIP Digital Archive
    Topics: Physics , Chemistry and Pharmacology
    Notes: Clusters of rare gas atoms provide an interesting setting for the study of the issue of quantum mechanical localization. The properties of these clusters of 2–7 atoms are calculated using variational Monte Carlo methods. To our knowledge, this is the first variational Monte Carlo study of localized clusters and new solidlike wave function forms, including shadow, multiple bond length, and Boltzmann-like wave functions, are reported. Diffusion Monte Carlo methods provide an independent, exact value of the ground state energy, useful as a check of the variational results. The properties of the variational wave functions, when analyzed in terms of probability distribution functions, quench studies, and visual examination of the wave functions, indicate delocalized helium and localized argon and neon clusters.
    Type of Medium: Electronic Resource
    Location Call Number Expected Availability
    BibTip Others were also interested in ...
  • 3
    Electronic Resource
    Electronic Resource
    College Park, Md. : American Institute of Physics (AIP)
    The Journal of Chemical Physics 99 (1993), S. 8183-8193 
    ISSN: 1089-7690
    Source: AIP Digital Archive
    Topics: Physics , Chemistry and Pharmacology
    Notes: The surface diffusion constant for hydrogen and deuterium on the palladium(111) surface is calculated using quantum mechanical transition state theory. The rate constants for diffusion into the subsurface layer are also calculated. Quantum effects are seen to be most important for the surface/subsurface transition and cause an inverse isotope effect in which the rate for deuterium is greater than the rate for hydrogen. The results of ground and excited state wave function calculations show localized hydrogenic states, despite large zero point energies, and that the preferred binding site can vary with isotope between surface and subsurface sites. In addition, estimates of the tunneling rate between the surface and subsurface are in qualitative agreement with the low temperature transition state results.
    Type of Medium: Electronic Resource
    Location Call Number Expected Availability
    BibTip Others were also interested in ...
  • 4
    Electronic Resource
    Electronic Resource
    College Park, Md. : American Institute of Physics (AIP)
    The Journal of Chemical Physics 101 (1994), S. 7048-7057 
    ISSN: 1089-7690
    Source: AIP Digital Archive
    Topics: Physics , Chemistry and Pharmacology
    Notes: We employ a unified molecular dynamics (MD), quantum mechanical approach to simulate the behavior of large collections of atoms at finite temperature. The nuclei are moved according to classical mechanics while the forces are computed via quantum mechanical models. Two approaches have been used: (1) the extended Hückel method, which is an approximate molecular orbital approach and (2) density functional theory based on the local density approximation and plane wave pseudopotential formulation. We compute properties from the MD trajectories of up to 4 ps duration for samples containing up to 250 atoms of lithium, sodium, and potassium. These results are compared to both previous calculations and experimental results.
    Type of Medium: Electronic Resource
    Location Call Number Expected Availability
    BibTip Others were also interested in ...
  • 5
    Electronic Resource
    Electronic Resource
    s.l. : American Chemical Society
    Journal of agricultural and food chemistry 6 (1958), S. 850-853 
    ISSN: 1520-5118
    Source: ACS Legacy Archives
    Topics: Agriculture, Forestry, Horticulture, Fishery, Domestic Science, Nutrition , Process Engineering, Biotechnology, Nutrition Technology
    Type of Medium: Electronic Resource
    Location Call Number Expected Availability
    BibTip Others were also interested in ...
  • 6
    Electronic Resource
    Electronic Resource
    College Park, Md. : American Institute of Physics (AIP)
    The Journal of Chemical Physics 86 (1987), S. 1748-1751 
    ISSN: 1089-7690
    Source: AIP Digital Archive
    Topics: Physics , Chemistry and Pharmacology
    Notes: In this paper, we report the results of ab initio calculations of photoelectron angular distributions and vibrational branching ratios for the (2+1) REMPI of H2 via the E,F 1Σ+g state, and compare these with the experimental data of Anderson et al. [Chem. Phys. Lett. 105, 22 (1984)]. These results show that the observed non-Franck–Condon behavior is predominantly due to the R dependence of the transition matrix elements, and to a lesser degree to the energy dependence. This work presents the first molecular REMPI study employing a correlated wave function to describe the Rydberg–valence mixing in the resonant intermediate state.
    Type of Medium: Electronic Resource
    Location Call Number Expected Availability
    BibTip Others were also interested in ...
  • 7
    Electronic Resource
    Electronic Resource
    College Park, Md. : American Institute of Physics (AIP)
    The Journal of Chemical Physics 84 (1986), S. 5504-5512 
    ISSN: 1089-7690
    Source: AIP Digital Archive
    Topics: Physics , Chemistry and Pharmacology
    Notes: We have studied the photoionization cross sections and photoelectron asymmetry parameters for ionization of the 1πg(X 2Πg), 5σg(A 2Σ+g), and 4σu(B 2Σ+u) levels of cyanogen using frozen-core Hartree–Fock photoelectron continuum orbitals. The main purpose of these studies has been to extend our understanding of the dynamics of shape resonances from earlier studies of diatomic and smaller polyatomic molecules to a larger polyatomic system. The results do, in fact, reveal a rich shape resonant structure in the electronic continuum of this polyatomic system. There is a low-energy σu resonance which, as expected, is the C–C analog of the l=3 shape resonance seen in N2(3σ−1g) and several other diatomics. In contrast to this diatomic-like behavior, the presence of the two CN groups in C2N2 results in a second σu and a σg resonance corresponding to linear combinations of a l=3 shape resonance localized on the CN sites. Moreover, our results also show a pronounced shape resonant behavior in the πu continuum, which, to our knowledge, has not been seen in smaller molecules.
    Type of Medium: Electronic Resource
    Location Call Number Expected Availability
    BibTip Others were also interested in ...
  • 8
    Electronic Resource
    Electronic Resource
    College Park, Md. : American Institute of Physics (AIP)
    The Journal of Chemical Physics 84 (1986), S. 6657-6661 
    ISSN: 1089-7690
    Source: AIP Digital Archive
    Topics: Physics , Chemistry and Pharmacology
    Notes: We report theoretical cross sections for direct photoionization of specific rovibrational levels of the B 1Σ+u electronic state of H2. The calculated cross sections differ considerably from values recently determined by resonant enhanced multiphoton ionization (REMPI) studies. In an attempt to understand the disagreement, we analyze in detail the REMPI dynamics and find that the multiphoton ionization probability is extremely sensitive to the spatial and temporal profiles of the laser pulses. Accurate characterization of laser profiles and their jitter is therefore necessary for a comparison between theory and experiment.
    Type of Medium: Electronic Resource
    Location Call Number Expected Availability
    BibTip Others were also interested in ...
  • 9
    Electronic Resource
    Electronic Resource
    [s.l.] : Nature Publishing Group
    Nature 181 (1958), S. 1478-1479 
    ISSN: 1476-4687
    Source: Nature Archives 1869 - 2009
    Topics: Biology , Chemistry and Pharmacology , Medicine , Natural Sciences in General , Physics
    Notes: [Auszug] Several workers* have prepared synthetic protein lignin complexes simulating soil humic acid. While the reports are somewhat conflicting, in general, these complexes were attacked and degraded by the soil mieronora with some difficulty. A number of protein-lignin complexes were prepared from ...
    Type of Medium: Electronic Resource
    Location Call Number Expected Availability
    BibTip Others were also interested in ...
  • 10
    Electronic Resource
    Electronic Resource
    [s.l.] : Nature Publishing Group
    Nature 179 (1957), S. 1131-1131 
    ISSN: 1476-4687
    Source: Nature Archives 1869 - 2009
    Topics: Biology , Chemistry and Pharmacology , Medicine , Natural Sciences in General , Physics
    Notes: [Auszug] Another clay mineral, attapulgite (pH. 8-5), intermediate in crystal structure between montmorillonite and kaolinite, has been studied using gelatin and cellulose dextrin (prepared from cellulose by degrading it with 72 per cent sulphuric acid)4 as the substrates. Gelatin alone (100 mgm.) and ...
    Type of Medium: Electronic Resource
    Location Call Number Expected Availability
    BibTip Others were also interested in ...
Close ⊗
This website uses cookies and the analysis tool Matomo. More information can be found here...