Quantum mechanical scattering calculations

Resonances in reactive collisions were first observed in quantum mechanical scattering calculations for the colllnear H + H2 reaction (1-9 for a review of early calculations on this system see reference 22. recent review of the quantum mechanical... 

The steplike CRP originally obtained (8) from quantum mechanical scattering calculations has also been reproduced by a trace formula that avoids explicit specification of asymptotic states (98,99) and by a method based on eigenvalues of a reaction probability operator (100). 

The authors are grateful to Yuri Volobuev for participation in early stages of the DH2 analysis and to Professor Ken Leopold for helpful discussions. The quantum mechanical scattering calculations were supported in part by the National Science Foundation. The variational transition state theory calculations were supported in part by the U.S. Department of Energy, Office of Basic Energy Sciences. 

We highlight some recent work from our laboratory on reactions of atoms and radicals with simple molecules by the crossed molecular beam scattering method with mass-spectrometric detection. Emphasis is on three-atom (Cl + H2) and four-atom (OH + H2 and OH + CO) systems for which the interplay between experiment and theory is the strongest and the most detailed. Reactive differential cross sections are presented and compared with the results of quasiclassical and quantum mechanical scattering calculations on ab initio potential energy surfaces in an effort to assess the status of theory versus experiment. 

These reactions have been studied by various theoretical methods, that is, classical trajectories, transition-state theory, and quantum mechanical scattering calculations. The accumulation of results from these studies provides a relatively complete description of this reaction system. 

Classical trajectories are being used extensively to study reactions involving four atoms in which the reaction in one direction is between an atom and a triatomic molecule and in the reverse direction between two diatomics. Concurrently, detailed experimental measurements are being reported and quantum mechanical scattering calculations are being done. At the current rate of activity we will soon have a broad and deep knowledge of these kinds of reactions. We will give only a brief overview of this work since a comprehensive review was published in 1996. ... 

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