The Coupled-Channels Integral-Equations Method in the Theory of Low-Energy Electron-Molecule Scattering

  • Michael A. Morrison


The part of this workshop that is devoted to electron-molecule collisions is concerned with two somewhat complimentary classes of approaches to this problem: L2-variational methods, such as the R-matrix and T-matrix methods, and eigenfunction-expansion methods, such as the close-coupling or coupled-channel method. The former approaches are discussed in accompanying articles by Schneider and by Fliflet. In this paper, we shall be concerned with the coupled-channels method for low-energy electron-molecule scattering.1–4 Various aspects of the physics of electron-molecule collisions have been discussed in detail elsewhere. Thus the present review will emphasize techniques for solving the problem. We first describe how to formulate and carry out such a calculation (Secs. II and III) and then suggest where likely pitfalls lie and ways to avoid them (Sec. IV). Since most of the applications to date of the coupled-channel method have employed approximate local potentials, the development in this paper will deal primarily with the solution of differential equations via an integral-equations algorithm. The case of integrodifferential equations (which arise when electron exchange effects are rigorously taken into account) will be discussed briefly in Sec. V.


Integrate Cross Section Internuclear Axis Integration Mesh Angular Basis Rotational Excitation Cross Section 


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Copyright information

© Plenum Press, New York 1979

Authors and Affiliations

  • Michael A. Morrison
    • 1
  1. 1.Department of Physics and AstronomyUniversity of OklahomaNormanUSA

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