This renewal award is made in the Organic Dynamics Program in support of the research of Drs. Gust and Moore at Arizona State University. The research deals with the design, synthesis and study of the photochemistry of multicomponent molecular systems which mimic natural photosynthetic electron and energy transfer processes. The systems which will be studied consist of porphyrins(P), carotenoid polyenes(C), quinones(Q) and electron donor molecules(D) joined together by chemical linkages which control the relative separation and orientation of the various moeities. The choice of moeity and linkages determines the function of the system. One of the proposed systems, of the form C-P-P-Q, is expected to undergo photoinitiated electron transfer which should ultimately lead to a long-lived energetic charge separated species. Another molecule of the type D-C-P-P-Q may be capable of demonstrating a stepwise two-electron charge separation. The broad objectives of the research are to help us understand how natural photosynthetic energy and electron transfer occur, to apply the basic chemistry and physics of photosynthesis to the design of artificial solar energy harvesting systems, and to develop methods for the design and synthesis of molecular electronic devices.
