TITLE

Comparison of quasiclassical and quantum dynamics for resonance scattering in the Cl+HCl→ClH+Cl reaction

AUTHOR(S)
Jakubetz, W.; Sokolovski, D.; Connor, J. N. L.; Schatz, G. C.
PUB. DATE
November 1992
SOURCE
Journal of Chemical Physics;11/1/1992, Vol. 97 Issue 9, p6451
SOURCE TYPE
Academic Journal
DOC. TYPE
Article
ABSTRACT
We present the results of quasiclassical trajectory (QCT) and quantum centrifugal sudden hyperspherical (CSH) scattering calculations for the Cl+HCl→ClH+Cl reaction using a semiempirical potential energy surface. In particular, we report state-to-state integral and differential cross sections in the vicinity of a transition state resonance that occurs at a total energy E of 0.642 eV. This resonance, which is labeled by the transition state quantum numbers (0,0,2), strongly perturbs the cross sections for the initial rovibrational state HCl(v=1, j=5), which was therefore considered in all our calculations. For E≥0.680 eV, which is well removed from the resonance energy, the QCT and CSH results are in good agreement, but for E near the resonance energy, important quantum effects are found in the integral cross sections, product state distributions, and differential cross sections. The CSH integral cross sections show smooth steplike increases for E≊0.642 eV, which are not seen in the QCT results. Associated with these steps are increased branching to the v’=0 product HCl vibrational state, and a strong propensity for the production of rotational states with j’=15 and 16 for v’=0. These features of the product energy partitioning are not present in the QCT results, although the correct rotational distributions are approximately recovered if the final vibrational action is constrained to match its quantum value. The CSH differential cross sections show a sudden shift from backward to sideward scattering between 0.642 and 0.660 eV, while the QCT cross sections remain backward peaked. An analysis of the ‘‘number of atom–diatom encounters,’’ during the course of a reactive collision, shows that there are chattering trajectories. These are associated with sideward scattering, but their probability is low and as a result they do not produce distinct features in the angular distributions. However...
ACCESSION #
7619531

 

Related Articles

  • Time-dependent quantum dynamics study of the Cl+H[sub 2] reaction. Yang, Ben-Hui; Ben-Hui Yang; Gao, Hong-Tao; Hong-Tao Gao; Han, Ke-Li; Ke-Li Han; Zhang, John Z. H.; Zhang, John Z.H. // Journal of Chemical Physics;7/22/2000, Vol. 113 Issue 4 

    We report rigorous quantum dynamics studies of the Cl+H[sub 2] reaction. The time-dependent wave packet calculations are performed on the semiempirical G3 and the new BW2 potential energy surfaces. Initial state-specific total reaction probabilities and cross sections are calculated and the...

  • A quantum mechanical and quasi-classical trajectory study of the Cl+H[sub 2] reaction and its isotopic variants: Dependence of the integral cross section on the collision energy and reagent rotation. Aoiz, F. J.; Ban˜ares, L.; Castillo, J. F.; Mene´ndez, M.; Skouteris, D.; Werner, H.-J. // Journal of Chemical Physics;Aug2001, Vol. 115 Issue 5, p2074 

    Quantum mechanical (QM) and quasi-classical trajectory (QCT) calculations have been performed for the Cl+H[sub 2], Cl+D[sub 2], Cl+HD→ HCl(DCl)+D(H) reactions in order to determine integral cross sections as a function of collision energy and for different reagent rotational quantum...

  • Full-dimensional quantum mechanical calculation of the rate constant for the H2+OH→H2O+H reaction. Manthe, Uwe; Seideman, Tamar; Miller, William H. // Journal of Chemical Physics;12/15/1993, Vol. 99 Issue 12, p10078 

    The cumulative reaction probability (CRP) (the Boltzmann average of which is the thermal rate constant) has been calculated for the reaction H2+OHH2O+H in its full (six) dimensionality for total angular momentum J=0. The calculation, which should be the (numerically) exact result for the assumed...

  • Quantum studies of Eley–Rideal reactions between H atoms on a graphite surface. Sha, Xianwei; Jackson, Bret; Lemoine, Didier // Journal of Chemical Physics;4/22/2002, Vol. 116 Issue 16, p7158 

    Results from electronic structure studies and quantum scattering calculations are presented for the reaction of gas-phase H atoms with H atoms adsorbed onto a graphite surface to form H[sub 2](g). H can chemisorb on graphite directly over a carbon atom, with the carbon puckering out of the...

  • Three-dimensional quantum mechanical study of the Li+HF→LiF+H process: Calculation of integral and differential cross sections. Baer, Michael; Last, Isidore; Loesch, Hans-Jurgen // Journal of Chemical Physics;12/1/1994, Vol. 101 Issue 11, p9648 

    In this work is presented a detailed quantum mechanical study of the Li+HF(v=0,j) →LiF(v’,j’)+H reaction in the low energy region 0.001≤Etr≤0.15 eV. The theoretical-numerical treatment was carried out within the inelastic jz approximation coupled with negative...

  • Effect of the geometric phase on the dynamics of the hydrogen-exchange reaction. Juanes-Marcos, Juan Carlos; Althorpe, Stuart C.; Wrede, Eckart // Journal of Chemical Physics;1/28/2007, Vol. 126 Issue 4, p044317 

    A recent puzzle in nonadiabatic quantum dynamics is that geometric phase (GP) effects are present in the state-to-state opacity functions of the hydrogen-exchange reaction, but cancel out in the state-to-state integral cross sections (ICSs). Here the authors explain this result by using topology...

  • Quantum resonance dynamics for the I+HI reaction in three dimensions: An adiabatic treatment using Jacobi coordinates. Grayce, Beverly B.; Skodje, Rex T. // Journal of Chemical Physics;11/15/1991, Vol. 95 Issue 10, p7249 

    The quantum mechanical resonance states for the I+HI chemical reaction on the Manz–Römelt LEPS (London–Erying–Polanyi–Sato) surface ‘‘A’’ are calculated in three dimensions for the case of total angular momentum equal to zero. The problem...

  • The reaction of CCl3 radicals and Cl atoms with hydrogen molecules. Xing, G.; Huang, X.; Bersohn, R.; Tsukiyama, K.; Katz, B. // Journal of Chemical Physics;2/22/1995, Vol. 102 Issue 8, p3169 

    A small amount of H atoms are observed as products of the reaction of Cl atoms generated by photodissociating Cl2 at 351 nm in the presence of H2. A much larger H atom concentration is detected when a mixture of H2 and CCl4 is photodissociated at 193 nm with an average kinetic energy of...

  • Spin-orbit quenching of Cl(2P1/2) by H2. Lique, François; Alexander, Millard H. // Journal of Chemical Physics;3/28/2012, Vol. 136 Issue 12, p124312 

    We report fully-quantum, time-independent, scattering calculations for the spin-orbit quenching of Cl(2P1/2) by H2 molecules at low and moderate temperature. Our calculations take into account chemical reaction channels. Cross sections are calculated for total energies up to 5000 cm-1 which are...

Share

Read the Article

Courtesy of THE LIBRARY OF VIRGINIA

Sorry, but this item is not currently available from your library.

Try another library?
Sign out of this library

Other Topics