Library

X
Language
Preferred search index
Number of Hits per Page
Default Sort Criterion
Default Sort Ordering
Size of Search History
Default Email Address
Default Export Format
Default Export Encoding
Facet list arrangement
Maximum number of values per filter
Auto Completion
Feed Format
Maximum Number of Items per Feed
Permalink If you want to be able to use settings permanently, you must save your settings and then set a Bookmark to the permalink
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
    Quasiclassical dynamics of the I2–Ne2 vibrational predissociation: A comparison with experiment (1996)
    College Park, Md. : American Institute of Physics (AIP)
    The Journal of Chemical Physics 104 (1996), S. 8405-8412 
    Details
    ISSN: 1089-7690
    Source: AIP Digital Archive
    Topics: Physics , Chemistry and Pharmacology
    Notes: The vibrational predissociation dynamics of the I2(B,v)–Ne2 complex is investigated for several vibrational levels of I2, using a quasiclassical trajectory approach. The time evolution of the population of nascent I2 fragments is calculated. A model is proposed which reproduces the results of the classical trajectories, and allows to obtain the lifetimes associated with the dissociation of the two van der Waals (vdW) bonds. The classical lifetimes are higher in general than the experimental ones of Zewail and co-workers [J. Chem. Phys. 97, 8048 (1992)]. The classical method appears to overestimate mechanisms of energy redistribution between the modes, which slow down the dissociation of the cluster. However, the behavior of the lifetimes with the initial iodine vibrational excitation is in very good agreement with experiment. A sequential path of fragmentation of the two weak bonds via direct predissociation is found to dominate, producing I2(B,v–2)+2Ne fragments. Although with smaller probability, alternative dissociation paths are observed involving statistical mechanisms of internal energy redistribution. In these paths, the energy initially transferred by the iodine heats the vdW modes without breaking the complex. Further energy transfer produces either simultaneous or sequential dissociation of the two weak bonds in a rather evaporative way, populating the v–2 and v–3 exit channels. © 1996 American Institute of Physics.
    Type of Medium: Electronic Resource
    URL: http://dx.doi.org/10.1063/1.471590
    Library Location Call Number Volume/Issue/Year Availability
    BibTip Others were also interested in ...
    Paper (German National Licenses)
    Fulltext
  • 2
    Electronic Resource
    Electronic Resource
    Application of a diabatic distorted wave approximation to the study of X⋅ ⋅ ⋅H2 (X=He, Ne, Ar) van der Waals molecules (1986)
    College Park, Md. : American Institute of Physics (AIP)
    The Journal of Chemical Physics 85 (1986), S. 2084-2088 
    Details
    ISSN: 1089-7690
    Source: AIP Digital Archive
    Topics: Physics , Chemistry and Pharmacology
    Notes: A diabatic rotational decoupling scheme is applied to X⋅ ⋅ ⋅H2 van der Waals molecules using the anisotropic potentials of Tang and Toennies [J. Chem. Phys. 68, 5501 (1978); 74, 1148 (1981)]. We have developed the method proposed by Beswick and Requena [J. Chem. Phys. 72, 3018 (1980)] in an entirely numerical way. Attention is focused on the rotational predissociating levels and on the shape resonances of these systems. Among these resonances, a narrow orbiting and a narrow overbarrier resonances are found for the complexes Ne–H2 and Ar–H2, respectively. They should be amenable to experimental observation in molecular beam scattering as well as infrared spectroscopic studies.
    Type of Medium: Electronic Resource
    URL: http://dx.doi.org/10.1063/1.451152
    Library Location Call Number Volume/Issue/Year Availability
    BibTip Others were also interested in ...
    Paper (German National Licenses)
    Fulltext
  • 3
    Electronic Resource
    Electronic Resource
    Rotational predissociation of (rare gas atom)–(slow rotating diatomic molecule) complexes (1987)
    College Park, Md. : American Institute of Physics (AIP)
    The Journal of Chemical Physics 87 (1987), S. 1054-1061 
    Details
    ISSN: 1089-7690
    Source: AIP Digital Archive
    Topics: Physics , Chemistry and Pharmacology
    Notes: We present an adiabatic angular approximation, closely related to the infinite order sudden approximation, to treat rotational predissociation of triatomic van der Waals complexes formed by a rare gas atom and a diatomic molecule that is treated as a rigid rotor. The metastable states of the complex are obtained as discrete solutions of the Schrödinger equation while the corresponding continuum solutions allow us to estimate the rates for rotational predissociation, within the framework of the Golden Rule approximation, after the relevant discrete-continuum dynamical couplings are calculated. Applications to the He–CO, He–N2, and He–O2 systems are presented.
    Type of Medium: Electronic Resource
    URL: http://dx.doi.org/10.1063/1.453338
    Library Location Call Number Volume/Issue/Year Availability
    BibTip Others were also interested in ...
    Paper (German National Licenses)
    Fulltext
  • 4
    Electronic Resource
    Electronic Resource
    A close-coupling infinite order sudden approximation (IOSA) to study vibrational predissociation of the HeI2 van der Waals molecule (1986)
    College Park, Md. : American Institute of Physics (AIP)
    The Journal of Chemical Physics 84 (1986), S. 4268-4271 
    Details
    ISSN: 1089-7690
    Source: AIP Digital Archive
    Topics: Physics , Chemistry and Pharmacology
    Notes: We apply in this paper a model related to the "infinite order sudden approximation'' to treat the vibrational predissociation of the HeI2 van der Waals molecule. For each configuration, the stretching motions within the complex are exactly solved in the close-coupling formalism. The bending motion is then considered in an approximate way and averaged predissociation rates are obtained. Our results are compared with the experiment and also with previous models.
    Type of Medium: Electronic Resource
    URL: http://dx.doi.org/10.1063/1.450048
    Library Location Call Number Volume/Issue/Year Availability
    BibTip Others were also interested in ...
    Paper (German National Licenses)
    Fulltext
  • 5
    Electronic Resource
    Electronic Resource
    Structure and dynamics of small I2 . . . Hen van der Waals clusters (n=1–9) (1990)
    College Park, Md. : American Institute of Physics (AIP)
    The Journal of Chemical Physics 92 (1990), S. 6504-6513 
    Details
    ISSN: 1089-7690
    Source: AIP Digital Archive
    Topics: Physics , Chemistry and Pharmacology
    Notes: Energetics and dynamics of van der Waals (vdW) I2⋅⋅⋅Hen clusters are studied in an approximate way by using a model that considers 2n+1 degrees of freedom, that is, the I2 stretch and the 2n stretching and bending modes of the He atoms restricted to move along a plane perpendicular to the I2 axis. For n=2,3 a configuration-interaction treatment is carried out to obtain energy levels. For n=4–8, ground-level energies are estimated from those corresponding to n=2,3 and the geometric relationships among the n vdW bonds. A quasiclassical trajectory approach is used to study the dynamics of these clusters, and lifetimes and half-widths for vibrational predissociation have been calculated for n=1–9. A large increase in the half-width of n=9 with respect to the cases n=1–8 is observed, which would imply the existence of a first coordination shell for He about I2 containing eight atoms. Also, it is found that the mechanisms of dissociation for these clusters become statistical as the number of vdW bonds increases.
    Type of Medium: Electronic Resource
    URL: http://dx.doi.org/10.1063/1.458285
    Library Location Call Number Volume/Issue/Year Availability
    BibTip Others were also interested in ...
    Paper (German National Licenses)
    Fulltext
  • 6
    Electronic Resource
    Electronic Resource
    Study of the electronic-to-vibrational energy transfer in the quenching process of Na*(3 2P) with N2(1Σ+g,v=0). A quantal close coupling calculation (1989)
    College Park, Md. : American Institute of Physics (AIP)
    The Journal of Chemical Physics 91 (1989), S. 155-161 
    Details
    ISSN: 1089-7690
    Source: AIP Digital Archive
    Topics: Physics , Chemistry and Pharmacology
    Notes: Electronic-to-vibrational energy transfer has been studied by solving numerically the close-coupling equations, in the T-shape configuration, on the two lowest electronic states of the Na–N2 system. The diabatic potential surfaces were taken from Archirel and Habitz while the interelectronic coupling was modeled by different Gaussian-type functions. Different sets of parameters for the coupling were used in order to study the final vibrational distributions of N2. Finally, partial quenching probabilities are presented and compared with previous theoretical and experimental works.
    Type of Medium: Electronic Resource
    URL: http://dx.doi.org/10.1063/1.457494
    Library Location Call Number Volume/Issue/Year Availability
    BibTip Others were also interested in ...
    Paper (German National Licenses)
    Fulltext
  • 7
    Electronic Resource
    Electronic Resource
    Study of the diffraction mediated selective adsorption through the close-coupling and diabatic distorted wave formalisms. Application to the 4He–Cu(110) system (1989)
    College Park, Md. : American Institute of Physics (AIP)
    The Journal of Chemical Physics 90 (1989), S. 3823-3830 
    Details
    ISSN: 1089-7690
    Source: AIP Digital Archive
    Topics: Physics , Chemistry and Pharmacology
    Notes: Two different formalisms, one based on close-coupling equations and other on the distorted wave approximation, have been applied to the low energy elastic scattering of 4He atoms by a corrugated copper surface, Cu(110). Diffraction intensities and energetic positions and half-widths (selective adsorption resonances) have been obtained and compared with experimental and previous theoretical results, respectively. For this trapping process, and within the close-coupling framework, a plot of the diffraction channels (open and closed) has turned out to be very useful and a good guide in order to know the disposition of them at each interesting angular region. Also, a very accurate method, already employed successfully to treat resonances in the vibrational and/or rotational predissociation of van der Waals molecules, has been found to be also adequate here.
    Type of Medium: Electronic Resource
    URL: http://dx.doi.org/10.1063/1.455839
    Library Location Call Number Volume/Issue/Year Availability
    BibTip Others were also interested in ...
    Paper (German National Licenses)
    Fulltext
  • 8
    Electronic Resource
    Electronic Resource
    Dissociation dynamics of I2⋅⋅⋅Nen van der Waals clusters (n=1–9): A quasiclassical approach (1991)
    College Park, Md. : American Institute of Physics (AIP)
    The Journal of Chemical Physics 94 (1991), S. 7868-7874 
    Details
    ISSN: 1089-7690
    Source: AIP Digital Archive
    Topics: Physics , Chemistry and Pharmacology
    Notes: The dynamics of vibrational predissociation (VP) of van der Waals (vdW) I2⋅⋅⋅Nen clusters is studied by means of a quasiclassical trajectory approach. We assume a near-equilibrium geometry that accounts for the I2 stretch and the stretching and bending modes of the rare gas atoms restricted to move along a plane perpendicular to the I2 axis. A sharp increase of the halfwidth is observed for n=9 together with certain stability of the n=8 cluster size with respect to dissociation. It would indicate the existence of a first coordination shell for Ne around I2 containing eight atoms. In addition, the dissociation results less and less efficient as n increases and statistical mechanisms become important for the cluster sizes studied.
    Type of Medium: Electronic Resource
    URL: http://dx.doi.org/10.1063/1.460122
    Library Location Call Number Volume/Issue/Year Availability
    BibTip Others were also interested in ...
    Paper (German National Licenses)
    Fulltext
  • 9
    Electronic Resource
    Electronic Resource
    An approximate quantal treatment to obtain the energy levels of tetra-atomic X ⋅⋅⋅ I2 ⋅⋅⋅ Y van der Waals clusters (X,Y=He,Ne) (1990)
    College Park, Md. : American Institute of Physics (AIP)
    The Journal of Chemical Physics 92 (1990), S. 496-507 
    Details
    ISSN: 1089-7690
    Source: AIP Digital Archive
    Topics: Physics , Chemistry and Pharmacology
    Notes: The structure of tetra-atomic X ⋅⋅⋅ I2 ⋅⋅⋅ Y van der Waals (vdW) clusters, where X,Y=He,Ne, is studied using an approximate quantal treatment. In this model the above complexes are treated as like diatomic molecules with the rare-gas atoms playing the role of electrons in conventional diatomics. Then a H2-like molecular-orbital formalism is applied, choosing the discrete states of triatomic systems I2 ⋅⋅⋅ X(Y) as molecular orbitals. Calculations at fixed configurations as well as including vdW bending motions restricted to the plane perpendicular to the I2 axis have been carried out for the sake of comparison with previous results. Finally, the restrictions are relaxed and the vdW bending motions are incorporated in a full way within the framework of a configuration interaction. The structure of these clusters is also studied through the probability density function.
    Type of Medium: Electronic Resource
    URL: http://dx.doi.org/10.1063/1.458451
    Library Location Call Number Volume/Issue/Year Availability
    BibTip Others were also interested in ...
    Paper (German National Licenses)
    Fulltext
  • 10
    Electronic Resource
    Electronic Resource
    On the coupling of rotovibrational motions in He–Li2 inelastic collisions (1991)
    College Park, Md. : American Institute of Physics (AIP)
    The Journal of Chemical Physics 95 (1991), S. 5024-5035 
    Details
    ISSN: 1089-7690
    Source: AIP Digital Archive
    Topics: Physics , Chemistry and Pharmacology
    Notes: He–Li2 interaction potentials, which explicitly include both angular anisotropy and internal vibrational coordinates, have been proposed recently in the literature by extracting them from laser-selected, crossed beam experiments and from the use of various perturbation expansions. In view of the importance of assessing as accurately as possible the dynamical coupling of such internal degrees of freedom during inelastic, low-energy collisions, the present study undertakes a detailed computational comparison of the various possible decoupling schemes which can be employed to treat the above processes. It is found that because of the rather weak nature of the interaction in the title system, nearly all schemes work reasonably well and can be used in scattering calculations. It is, however, shown that the previously suggested potentials need to be modified extensively in order to yield cross sections which agree with the experimental findings.
    Type of Medium: Electronic Resource
    URL: http://dx.doi.org/10.1063/1.461690
    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...