Aldehyde Photolysis Reactions in the Gas Phase and on Ice Film

Health Research Incorporated/New York State Department Of Health, Menands NY

Investigators

Abstract

This project entails laboratory research on the formation of radicals from the photolysis of aldehydes, both in the gas phase and adsorbed on ice surfaces. Aldehydes are known to be important sources for free radicals, especially "odd hydrogen" (HOx) species that play essential roles in the oxidative capacity of the troposphere and lower stratosphere. Experimental techniques include laser photolysis followed by formyl radical detection using Cavity Ring-Down Spectroscopy (CRDS) and detection of other products by step scan Fourier Transform InfraRed spectroscopy (FTIR). The study addresses two separate, but related, reaction series: the photolysis of aliphatic and unsaturated dialdehydes in the gas phase, and the photolysis of formaldehyde and acetaldehyde on ice surfaces (as a surrogate for snow). Broader community impacts are addressed as follows. This work involves a contribution to interdisciplinary (surface chemical morphology and gas phase kinetics) science, will advance fundamental understanding of homogeneous and heterogeneous photolysis of aldehydes and could potentially bring quantitative insight to the current discussion of snow pack photochemical processes, considered to be of high relevance to climate change. The staffing plan includes a postdoctoral researcher and graduate student, and the principal investigator will include technical methodology and research findings into her university teaching coursework.