Dr. Catherine J. Murphy, of the University of South Carolina, is supported by the Inorganic, Bioinorganic and Organometallic Chemistry Program under a Faculty Early Career Advancement Award for the study of uses of luminescence as a probe of surface structure. Three areas are targeted: (1) Trisdiimine ruthenium(II) complexes will be designed such that luminescence will be observed only when one of the diimine ligands is of the appropriate length to fit a cavity in a large molecule such as DNA that is formed as a result of tertiary structure. (2) The known sensitivity of the luminescence of "quantum dots" of cadmium sulfide to the nature and amount of surface adsorbate will be investigated as a means of determining the nature of the interaction of DNA with these particles. It is hypothesized that DNA that can bend will adsorb to particles that are of the appropriate diameter and that this adsorption can be monitored by changes in the luminescence of the particles. Distances between the ends of DNA molecules wrapped about suitably sized particles may be further investigated by the extent to which energy transfer between molecular tags on the two ends of the duplex (fluorescein and rhodamine) occurs. (3) Synthesis of hollow "quantum dot" cadmium sulfide particles will be attempted in an effort to model the luminescence reported for porous semiconductor particles. Optical/structure relationships for these particles will be used to develop a model for the electronic structure of porous semiconductors. The teaching plan outlines several ways in which materials chemistry will be introduced into the undergraduate and graduate curricula through formal course work and through both undergraduate and graduate research. Also detailed are plans to foster the development of female scientists through interactions with women's organizations on campus and in local high schools and middle schools. Luminescence is a unique property of certain classes of molecules in whic h the absorption of light results in emission of light, usually of a longer wavelength. The wavelength and intensity of such luminescence is generally very sensitive to the environment about the absorbing molecule. This research aims to utilize the luminescence of several materials to probe the structures of their environments. These applications may provide unique information about the structure of certain types of DNA that is not readily determined by other techniques. The teaching program is designed to increase the exposure of undergraduate and graduate students to materials chemistry and to foster the development of female scientists.
