Classical trajectory and statistical adiabatic channel study of the dynamics of capture and unimolecular bond fission. VI. Properties of transitional modes and specific rate constants k(E,J)

Maergoiz, A. I.; Nikitin, E. E.; Troe, J.; Ushakov, V. G.
September 2002
Journal of Chemical Physics;9/1/2002, Vol. 117 Issue 9, p4201
Academic Journal
Transitional modes in simple unimolecular bond fission and in the reverse recombination reactions are characterized quantitatively by statistical adiabatic channel (SACM) and classical trajectory (CT) calculations. Energy E- and angular momentum J-specific numbers of open channels (or activated complex states) W(E,J) and capture probabilities w(E,J) are determined for a series of potentials such as ion—dipole, dipole-dipole, and various model valence potentials. SACM and CT treatments are shown to coincide under classical conditions. Adiabatic as well as nonadiabatic dynamics are considered. The dominant importance of angular momentum couplings is elaborated. A sequence of successive approximations, from phase space theory neglecting centrifugal barriers E[sub 0](J), via phase space theory accounting for centrifugal barriers E[sub 0](J), toward the final result, expressing the effects of the anisotropy of the potentials by specific rigidity factors f[sub rigid](E,J), is described. This approach emphasizes the importance to characterize the employed potentials by their centrifugal barriers E[sub 0](J). The derived specific rigidity factors f[sub rigid](E,J) are consistent with previously calculated thermal rigidity factors f[sub rigid](T). The present approach properly accounts for angular momentum conservation and, at the same time, facilitates the calculation of specific rate constants k(E,J) and falloff curves for unimolecular bond fission and the reverse radical recombination reactions.


Related Articles

  • The Present State of Cluster Radioactivity Research. Tretyakova, S.P.; Ogiobiin, A.A.; Pik-Pichak, G.A. // Physics of Atomic Nuclei;Sep2003, Vol. 66 Issue 9, p1618 

    Complete mass distributions of the energetically allowed decays of nuclei with A > 112 were calculated including the known regions of cluster radioactivity and cold fission. These processes represent different branches of the more general family of cold decays. A short review of the current...

  • Exit-channel dynamics in barrierless unimolecular reactions: Criteria of vibrational adiabaticity. Pavlov-Verevkin, V. B.; Lorquet, J. C. // Journal of Chemical Physics;8/15/2005, Vol. 123 Issue 7, p074311 

    Conversion of translational into vibrational energy during the last step of a unimolecular reaction is brought about by the curvature of the reaction path. The corresponding coupling is analyzed by an angle-action reaction path Hamiltonian (RPH). The accuracy of the vibrational adiabatic...

  • On the existence of a thermal continuum in nonadiabatic magnetohydrodynamic spectra. Van der Linden, R. A. M.; Goossens, M.; Goedbloed, J. P. // Physics of Fluids B: Plasma Physics;Apr91, Vol. 3 Issue 4, p866 

    The linear magnetohydrodynamic (MHD) spectrum of an infinite straight cylinder is investigated, taking nonadiabatic terms in the energy equation into account. It is shown that in nonideal MHD, a new continuum arises. Unlike the ‘‘classical’’ Alfvén and slow continua,...

  • Nonadiabatic Effects in the Phonon Spectrum of Metal Compounds. Morosov, A. I. // JETP Letters; 

    It is shown that nonadiabatic corrections to the dispersion law of optical phonons in the region of small wave vectors in the case of branches, for which the vibration with a zero wave vector is not accompanied by the appearance of a dipole moment in the ionic lattice, are significant for all...

  • Energy-Casimir and Energy-Lagrange Methods in the Study of Nonlinear Symmetric Stability Problems. Mu; Vladimirov, V. // Journal of the Atmospheric Sciences;2/1/99, Vol. 56 Issue 3, p400 

    Presents information on a study which investigated nonlinear symmetric stability problems in atmospheric dynamics. Stability of moist adiabatic system; Stability of the model with the northward component of the earth's rotation; Discussion of results.

  • Mixed convection on a vertical needle with heated tip. Wang, C. Y. // Physics of Fluids A;Apr90, Vol. 2 Issue 4, p622 

    The mixed convection on a vertical slender adiabatic paraboloid with a tip heat source is studied. The boundary layer equations admit similarity solutions that are governed by a nondimensional free-stream parameter ? and a heat source parameter a. Numerical results show for aiding flow (a>0) the...

  • On the Adiabatic Theorem in Quantum Mechanics. Chirkov, A. G. // Technical Physics Letters;Feb2001, Vol. 27 Issue 2, p93 

    The adiabatic and postadiabatic approximations, as well as the adiabatic and nonstationary perturbation theories, are constructed using a canonical averaging method under the assumptions which are more general than those used in the existing theories. An asymptotic evaluation of the proximity of...

  • Time-energy coherent states and adiabatic scattering. Avron, J. E.; Elgart, A.; Graf, G. M.; Sadun, L. // Journal of Mathematical Physics;Jul2002, Vol. 43 Issue 7, p3415 

    Coherent states in the time-energy plane provide a natural basis to study adiabatic scattering. We relate the (diagonal) matrix elements of the scattering matrix in this basis with the frozen on-shell scattering data. We describe an exactly solvable model, and show that the error in the frozen...

  • Adiabatic and strictly diabatic potential curves of He2+2. Kolbuszewski, Marcin; Gu, J.-P. // Journal of Chemical Physics;11/1/1995, Vol. 103 Issue 17, p7649 

    Adiabatic and strictly diabatic potential curves were calculated for the two lowest electronic states of He22+. The diabatization procedure leads to a repulsive diabatic curve dissociating to He+ + He+ and a bound curve dissociating to He2+ + He, crossing at the internuclear distance of 1.55...


Read the Article


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

Try another library?
Sign out of this library

Other Topics