Photochemistry of Atmospheric Particles

Abstract

Given the considerable interest in aerosol particles in the atmosphere as these particles play a key role in health, climate, and chemistry, there is an outstanding need for fundamental molecular studies of a wide range of aerosol processes. In the past, there has been a tremendous amount of interest in heterogeneous atmospheric chemistry, that is, reactions that are mediated by liquid or solid aerosol particles. Given the demonstrated importance of heterogeneous thermal chemistry in the atmosphere, it is surprising how little attention has been directed toward the photochemistry of atmospheric particles, that is, reactions initiated or significantly enhanced with light. This section focuses on the photochemistry of atmospheric particles. An important aspect of this is to develop a molecular scale level understanding of photochemistry in the aerosol environment and on surfaces, including details of the modifications to ground and excited electronic states of surface bound species and the ramifications for the product branching ratio.