Transfer of Vibrational Energy from Highly Excited Butyl Radical. Part 1. Relative Collision Diameters of Homologous n-Perfluoro Alkane Bath Molecules. Part 2. Structural Effects on the Magnitudes of the Relative Collision Diameters.

Abstract

Vibrationally excited n-butyl-2 radicals were collisionally deactivated by a homologous series of perfluoro-n-alkane bath molecules, CF4 to C8F18, at 298K and 195K. Increments in collision diameter were determined per CF2 group. Relative collision diameters referenced to cis-butene-2 were measured. Comparison of results at both temperatures indicate that the temperatures indicate that the temperature dependence of collision diameters does not follow the prediction of the 6-12 potential. Relative collision diameters for energy transfer were measured at room temperature in the butyl-2 system for substituted and cyclic fluorocarbon molecules. Three generalizations are illustrated by the data. (1) Branching of fluoroalkanes causes a decrease of the collision diameter. (2) Cyclization of the fluoroalkane chain decreases the effective size. (3) Introduction of terminal double bonds decreases the size. A simple equivalent sphere model based on the longest end-to-end carbon chain systemizes the relative collision diameters of related molecules. (Modified author abstract)

Document Details

Document Type
Technical Report
Publication Date
May 01, 1974
Accession Number
AD0778363

Entities

People

  • An-nan Ko
  • Benton Seymour Rabinovitch
  • R. C. Ireton

Organizations

  • University of Washington

Tags

DTIC Thesaurus Topics

  • Abstracts
  • Collisions
  • Diameters
  • Energy
  • Energy Transfer
  • Fluorinated Hydrocarbons
  • Fluoropolymers
  • Macromolecules
  • Molecules
  • Polymers
  • Terminals

Readers

  • Molecular Photonics/Laser Physics
  • Polymer Science and Technology
  • Thermal Physics or Thermal Science.