Knowledge Bank

An intracavity laser absorption apparatus has been constructed to monitor the time-resolved production and decay of transient reaction products such as free radicals. Since time-resolved intracavity detection (TRILD) derives from absorption, predissociated radicals are readily monitored. The operational principles of the apparatus will be described with special attention given to its sensitivity and linearity of response for detecting discretely absorbing radicals. The capability of TRILD for obtaining new kinetic and spectroscopic information on radicals will also be presented. The focus of the talk will then turn to the application of TRILD for obtaining time resolved information on the reaction dynamics of HCO formation in the photolysis of acetaldehyde. Specifically, the rates of formation and decay, the relative quantum yields, and the energetic onsets for radical formation will be presented for the HCO/acetaldehyde system.