Abstract:

Nitroaromatics are a class of organic molecules that have historically shown great utility in agricultural, pharmaceutical, and explosives industries. Though their use in pesticides has been phased out in the United States, studies of atmospheric aerosol have shown that a significant amount of these molecules still persist in the environment. A subclass of these molecules called nitrophenols have been shown to form naturally through the combustion of plant material. This process, called biomass burning, can produce individual nitrophenol concentrations that reach as high as 100 nanograms per cubic meter. Since these molecules are also often strong light absorbers, they often are responsible for the significant portion of visibility degradation by atmospheric aerosol. This dissertation provides a detailed analysis of the photochemistry of nitrophenols and other nitroaromatic systems. Isomeric differences are evaluated for both nitrophenols and nitroindoles. The breadth of these analyses, ranging from solutions to solid organic glasses to aerosol, culminates in a deeper understanding of the atmospheric fate of this class of molecules.