| The interaction of light with matter has demonstrated itself as a useful tool for investigating the physicochemical properties of many organic and inorganic chemical systems. The present work describes the significance of these interactions in identifying and creating chemical systems based on these principles. The first chapter describes the molecular basis of photophysics, with a discussion of several quantitative relationships pertinent to the dissertation. Chapter 2 details the syntheses and instrumentation employed.; Chapter 3 discusses energy transfer from [Ru(bpy)3] 2+ to nile blue A in aqueous solution in the presence of sodium dodecyl sulfate. At SDS concentrations below the critical micelle concentration, non-covalently assembled aggregates are formed which permit energy transfer at optically dilute (10 μM) concentrations with near 100% efficiency. The excited state lifetime disparity between the donor and acceptor results in the lengthening of the photoluminescence lifetime of the sensitized emission observed from nile blue A.; Chapter 4 discusses the electroluminescence of three rhenium(I) complexes in thin-film devices. Films of less than 100 nm thickness prepared on conductive glass substrates exhibit yellow luminescence under the influence of an applied potential. The emisisons display switching times which are synchronous with changes in applied potential. Stable light output can be observed over 24 hours of continuous operation at an applied bias of 4.0 V.; Chapter 5 details the preparation and photophysical characterization of mercaptosuccinic acid-capped cadmium sulfide and zinc sulfide semiconductor nanoparticles. Using a room-temperature synthesis, these particles are easily prepared from air-stable precursors and isolated as solids. Post-synthetic modification with aqueous metal ions enhances the spectral emission characteristics of these nanoparticles, consistent with surface modification of electronic trap states.; Chapter 6 highlights a new approach toward luminescent metal-organic Ru(II) complexes that concurrently harvest visible-light and display room temperature excited state lifetimes between 16 and 115 μs. The lifetime depends upon the solvent and the number of 4-piperidinyl-1,8-naphthalimide (PNI) chromophores present in the structure. Once produced by direct excitation or singlet energy transfer, the 1MLCT excited state intersystem crosses to multiple triplet states (3MLCT and 3PNI) that are in thermal equilibrium at room temperature. |
