Energy and Chemical Change.

Abstract

The information theoretic approach to branching ratios has been applied to a number of different processes. The main practical conclusion of this work is that for direct, exoergic reactions with low activation barriers, even in the absence of any other knowledge, the 'prior' branching ratio, which is very easy (slide rule) to estimate, already provides a useful guide. Exact quantal close coupling computations were carried out for atom-atom collisions. Comparisons were carried out with more approximate (e.g., Landau-Zener) treatments leading to practical conclusions regarding the coupling constants for such processes. The information theoretic analysis and synthesis of cross sections for rotational energy transfer in atom-diaton collision was studied in considerable detail. It was found possible to simulate an entire matrix of state-to-state cross sections by two constants. One of the two is just a scale factor for the absolute magnitude of the cross sections. The relative magnitudes are governed (to the first approximation) by a single parameter. It was found possible to provide ready estimates for this parameter which measures the importance of the energy 'mismatch' in the collision. The concept of the 'prior' distribution was clarified.

Document Details

Document Type
Technical Report
Publication Date
Dec 27, 1976
Accession Number
ADA035695

Entities

People

  • R. B. Bernstein
  • R. D. Levine

Organizations

  • University of Texas at Austin

Tags

Communities of Interest

  • Materials and Manufacturing Processes

DTIC Thesaurus Topics

  • Celestial Brightness
  • Collisions
  • Computations
  • Couplings
  • Energy
  • Energy Transfer

Fields of Study

  • Physics

Readers

  • Computational Modeling and Simulation
  • Molecular Photonics/Laser Physics