# Reactive Scattering Resonances and their Physical Interpretation: The Vibrational Structure of the Transition State

## Abstract

Quantum mechanical structure in reaction-probability-*versus*-energy curves for a realistic potential energy surface was first observed about a decade ago,^{1,2} for the collinear H + H_{2} system. Such structure had been previously found for a potential energy surface having sharp edges,^{3} made of piecewise-constant potentials, but in one-mathematical-dimensional (1MD) barrier problems, structure in transmission-probability-*versus*-energy curves^{4} is known to disappear when a rectangular barrier is replaced by one which is sufficiently “rounded”, such as parabolic^{5,6} or Eckart^{6,7} barriers, and is attributed to edge diffraction effects. The structure in the collinear H + H_{2} results on a smoothly varying surface, at energies above the vibrational excitation threshold of reaction products, was guessed^{1b} as being due to interference effects between different reaction paths, a guess subsequently confirmed by a quantum mechanical lifetime analysis^{8} and a semiclassical calculation.^{9} The former indicated the concomitant presence of and interference between direct and dynamic resonance (Feshbach^{10}) processes. The mechanism of such resonances was attributed to the existence of wells in the vibrationally adiabatic potentials along the minimum energy path.^{2b}

## Keywords

Potential Energy Surface Reaction Probability Translational Energy Exact Quantum Minimum Energy Path## Preview

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## References

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