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Wang D Huo WM Dateo CE Schwenke DW Stallcop JR 《The Journal of chemical physics》2004,120(13):6041-6050
We report a detailed three-dimensional time-dependent quantum dynamics study of the state-to-state N+N(2) exchange scattering in the 2.1-3.2 eV range using a recently developed ab initio potential energy surface (PES). The reactive flux arrives at the dividing surface in the asymptotic product region in a series of six packets, instead of a single packet. Further study shows that these features arise from the "Lake Eyring" region of the PES, a region with a shallow well between two transition states. Trappings due to Feshbach resonances are found to be the major cause of the time delay. A detailed analysis of the Feshbach resonance features is carried out using an L(2) calculation of the metastable states in the "Lake Eyring" region. Strong resonance features are found in the state-to-state and initial state selected reaction probabilities. The metastable states with bending motions and/or bending coupled with stretching motions are found to be the predominant source of the resonance structure. Initial state selected reaction probabilities further indicate that the lifetimes of the metastable states with bending motions in the "Lake Eyring" region are longer than those of states with stretching motions and thus dominate the reactive resonances. Resonance structures are also visible in some of the integral cross sections and should provide a means for future experimental observation of the resonance behavior. A study of the final rotational distributions shows that, for the energy range studied here, the final products are distributed toward high-rotational states. Final vibrational distributions at the temperatures 2000 and 10,000 K are also reported. 相似文献
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Harry Partridge Charles W. Bauschlicher James R. Stallcop 《Journal of Quantitative Spectroscopy & Radiative Transfer》1985,33(6):653-655
Potential energy curves for the , and states of N+2 that dissociate to N () and , have been determined from a complete active space self-consistent field calculation. The state is found to be significantly bound (De = 2.68 eV) with a minimum at 1.72 Å. 相似文献
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Billman Kenneth W. Stallcop James R. Öke Gülay 《Applied Physics A: Materials Science & Processing》1976,10(3):251-254
Applied Physics A - In a recent publication in this journal, Öke described an experiment designed to measure the total absorption coefficients for 0.6328- and 1.15-μm He?Ne laser... 相似文献
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Transport cross sections and collision integrals are tabulated for a wide range of energies and temperatures for the interactions
B–B and Al–Al. For aluminum, a semiclassical approximation was used to determine the scattering phase shifts from which the
transport cross sections were calculated. For boron, the smaller reduced mass and the deep potential wells required the phase
shifts at lower energies to be determined from a numerical solution of the time-independent Schroedinger equation; the semiclassical
approximation was used at higher energies where the two methods agree. The variations of the collision integrals for viscosity
and diffusion are presented graphically as a function of temperature. The results are applied to estimate the transport properties
of gallium.
Received: 9 July 1999 / Accepted: 18 August 1999 / Published online: 2 November 1999 相似文献
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James R. Stallcop 《Chemical physics》1974,5(3):456-463
Semiclassical collisions of an atom with a rigid-rotor molecule are examined in the sudden approximation. The rotational transition probability is shown to be variant with respect to the choice of orientation for the molecular coordinate system; this fact contradicts recently reported results of a computer analysis. The present analysis may lead to an improved interpretation of recent molecular beam measurements. 相似文献
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