On the basis of progress made during the current grant period, we propose to continue our investigation on pericyclic chemiluminescence derived from energy-rich dimers of benzene. 1. We propose to develop chemical methodology for the new syntheses of 4n dimers of benzene. One goal is to achieve efficient syntheses of these compounds in appreciable quantities for chemical investigations. The second goal is to explore the possibility of sensitized chemiluminescence from these dimers via the Schuster's CIEEL mechanism. 2. We propose to synthesize new mixed dimers of benzene and anthracene which (a) may yield more energy in their thermolyses than the known chemiluminescent compounds synthesized previously in our laboratory, (b) may yield an anthracene which has a lower excited state than these known compounds, and (c) may give rise to a more polar transition state in their thermolyses than these compounds. The relationships between these factors with the chemiluminescence efficiency will be studied in order to achieve a better understanding of the important phenomenon of chemiluminescence and/or biolouminescence in general. If we are able to develop new efficient chemiluminescent processes, these may have potentially significant applications. Furthermore, the chemistry of these benzene dimers may lead to a better understanding of the reactivities of small-ring compounds which possess many important biological properties.