Crossed Molecular Beam Studies.

Abstract

This report summarizes three of investigations: 1) studies of van der Waals collision dynamics, 2) laser spectroscopy study of rotational vibrational relaxations, and 3) angular correlations in chemical reactions. A cross molecular beam apparatus was used to study several van der Waals bond exchange reactions. These collisions involving extremely weak interactions were found to have product velocity distributions which resemble those from several ion molecular reactions which occur at very high collision energy. This led to the theoretical development of a scattering model which should be applicable to a wide range of reactive and inelastic collision processes at kinetic energies higher than the bond strengths. In another effort, laser induced fluorescence experiments were performed to measure the rotational and vibrational temperatures of molecular iodine seeded in beams of helium, argon, or nitrogen expanded from a supersonic nozzle. The results demonstrated the utility of seeded iodine fluorescence as a diagnostic for pulse shape and collisional relaxation in pulsed supersonic beams. Lastly, theoretical calculations dealing with rotational orientation in molecular collisions resulted in the formulation of a correlation analysis which offers a means to obtain information about collision dynamics that would otherwise be lost by averaging over the initial impact parameters and molecular orientations.

Document Details

Document Type
Technical Report
Publication Date
Apr 01, 1987
Accession Number
ADA183166

Entities

People

  • D. R. Herschbach

Organizations

  • Harvard University

Tags

Communities of Interest

  • Materials and Manufacturing Processes

DTIC Thesaurus Topics

  • Chemical Reactions
  • Collisions
  • Correlation Analysis
  • Dynamics
  • Energy
  • Exchange Reactions
  • Fluorescence
  • Kinetic Energy
  • Kinetics
  • Laser Induced Fluorescence
  • Laser Spectroscopy
  • Lasers
  • Molecular Beams
  • Orientation (Direction)
  • Supersonic Nozzles
  • Vibrational Relaxation

Fields of Study

  • Physics

Readers

  • Pulsed Power and Plasma Physics.
  • Quantum Chemistry
  • Quantum spin resonance or Electron Paramagnetic Resonance spectroscopy.

Technology Areas

  • Directed Energy
  • Directed Energy - Lasers
  • Hypersonics
  • Hypersonics - Hypersonic Flight