Infrared chemiluminescence investigation of fluorine atom substitution reactions

Abstract

The arrested relaxation infrared chemiluminescence technique has been used to investigate the fluorine atom substitution reactions of various olefinic and aromatic compounds. Analysis of the infrared emission spectra of the reaction products allows the determination of the product vibrational energy distribution. The observed vibrational energy distributions are compared to the distributions which would be obtained if the products exhibited statistical partitioning of the reaction energy. It was found that for all aromatic substrates studied and for olefinic substrates in which F was substituted for Cl or Br, the products exhibited statistical vibrational energy distributions, while nonstatistical distributions were obtained for olefinic substrates in which F was substituted for H or CH₃. These results are discussed within a framework of exit channel effects on product energy distributions, and the effects of postcollision intramolecular relaxation.