Classical Trajectory Methods in Molecular Collisions

  • Richard N. Porter
  • Lionel M. Raff
Part of the Modern Theoretical Chemistry book series (MTC, volume 2)


The dynamics of a molecular scattering process is described in exact terms by the solutions to the Schrödinger equation in which the kinetic energy and the electrodynamical interactions of all the nuclei and electrons of the colliding partners are used. If the process to be studied can be assumed to be adiabatic, the Born-Oppenheimer separation can be invoked, and the Schrödinger equation for the scattering is reduced to the problem of nuclear motion on a potential energy surface known as a function of all the internuclear distances. The accuracy of quantum mechanical calculations of the measurable attributes of molecular collisions is limited only by the accuracy of the potential energy surface and by the number of basis functions that can be afforded in terms of computer core storage size and processing time. The technical and economic questions are therefore
  1. 1

    How accurate must a calculation be in order to test predictions of a given theory against a given experimental result, and how is this accuracy most efficiently achieved?

  2. 2

    What calculational expense is commensurate with the scientific value of the result?



Potential Energy Surface Impact Parameter Trajectory Calculation Molecular Collision Rotational Quantum Number 
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Copyright information

© Springer Science+Business Media New York 1976

Authors and Affiliations

  • Richard N. Porter
    • 1
  • Lionel M. Raff
    • 2
  1. 1.Department of ChemistryState University of New YorkStony BrookUSA
  2. 2.Department of ChemistryOklahoma State UniversityStillwaterUSA

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