The photophysics of fullerene derivatives, catenanes and stilbene analogs

Chapter 1. General introduction.; Chapter 2. The examination of the photophysical properties of two ring-opened C₆₀ derivatives, both of which possess a sizable orifice. The photophysical parameters for these compounds such as T-T absorption, triplet energy and singlet oxygen quantum yield were compared to those for C₆₀. It was shown that the parameters of these unique molecules correlate well with those of the parent molecule, thus proving that the presence of an orifice in the C₆₀ cage does not fully disrupt the fullerene behavior.; Chapter 3. The effect of decreasing the conjugated area of C₆₀, via increasing amounts of functionalization, on its photophysics was studied. Using a series of seven homologous derivatives containing dialkyl malonate addends, an inverse linear relationship was observed between several key photophysical parameters (i.e. triplet energy, triplet quantum yield, and singlet oxygen quantum yield etc.) and the number of addends.; Chapter 4. An attempt is made to use photophysical methods, in particular photoinduced electron transfer, to gain insight into the molecular motion of [2]catenanes. The [2]catenanes studied here possess an easily-oxidized tetrathiafulvalene moiety, and it was found that C₆₀ was an excellent tool for initiating and studying this electron transfer. Although the transient spectra of the oxidized species could be readily observed, it was shown that the rate of this motion was either faster than the detection limit of the apparatus employed or the spectrum of the moved product was very similar to the initial one.; Chapter 5. A group of stilbene derivatives bearing anthryl or quinolinyl groups were studied using flash photolytic and steady-state techniques. It was shown that the observed photophysics for these molecules were a composite of the behaviors expected for stilbene and anthracene. In addition, like some anthracenes, it was discovered that both the singlet and triplet excited states could participate in the production of singlet oxygen, and that the solvent polarity affects this behavior. Finally, it was shown that the placement of the heteroaromatic substituent in the anthryl group played a vital role in the observed photophysics.