Time resolved Intracavity Laser Absorption Spectroscopy of Free Radicals

Abstract

Intracavity Laser Absorption Spectroscopy (ICLAS) combined with flash photolysis has been used during some years for spectroscopic identification of free radicals and for investigations of different types of radicals elementary gas phase processes. Several various types of experemental setups created are described. These setups differ from each other by the sensitivity, time resolution and by a spectral range of probing laser used. Measurements results of light absorbtion cross sections of $NH_{2}, HCO, HNO$ and $HO_{2}$ radicals, of vibrational relaxation of $NH_{2}$ and HCO radicals at collisions with monoatomic and polyatomic species, of elementary chemical reaction of $NH_{2}, HCO, HSO, HNO, PH_{2}, HO_{2}$ and $CH_{3}O_{2}$ radicals with radicals and stable molecules, heterogeneous decay of $NH_{2}$ and HNO are presented.