Energy Transfer Processes in Iodine Lasers

Abstract

The near resonant electronic energy transfer process I(2P3/2) + O2(alpha) left & right arrow I(2P1/2) + O2(X) is of central importance in COIL systems. The low temperature kinetics were characterized by studies of I(2P1/2)+O2 quenching at temperatures near 150K. As a component of this effort, sensitive LIF detection of I(2P1/2) was demonstrated. A quenching rate constant of (4.5+/-0.5)x10(exp -12 cu cm /s was obtained, which was appreciably smaller than the values used in current computer models. Ab initio calculations for I+O2 show that transfer is mediated by potential energy surface crossings that occur at short-range. Vibrational relaxation of I2(X) influences the efficiency of COIL systems. Ro-vibrational relaxation rate constants were measured for a range of collision partners (He, Ar, N2, O2, Cl2, I2, H2O). Overall, the inelastic collision dynamics were consistent with the predictions of classical trajectory models. Vibrational relaxation at low temperatures (<20 K) was examined in a free-jet expansion. Energy transfer from NCl(alpha) to 12 was examined. Although quenching of NCl(alpha) was near gas kinetic, preliminary results suggest that E-V transfer is inefficient. Ab inito calculations for Cl3, attempts to detect bound trihalogen intermediates, and new spectroscopic data for the D'-A' system of Br2 are described.

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Document Details

Document Type
Technical Report
Publication Date
Dec 28, 1997
Accession Number
ADA335731

Entities

People

  • Michael C Heaven

Organizations

  • Emory University

Tags

DTIC Thesaurus Topics

  • Chemical Oxygen Iodine Lasers
  • Collisions
  • Detection
  • Dynamics
  • Energy
  • Energy Transfer
  • First Principles Calculations
  • Kinetics
  • Laser Beams
  • Laser Induced Fluorescence
  • Lasers
  • Low Temperature
  • Measurement
  • Potential Energy
  • Spin-Orbit Interaction
  • Two Dimensional
  • Vibrational Relaxation

Fields of Study

  • Physics

Readers

  • Analytical Mechanics
  • Molecular Photonics/Laser Physics
  • Quantum Chemistry

Technology Areas

  • Directed Energy
  • Directed Energy - Lasers
  • Microelectronics