This Small Grant for Exploratory Research is made by the Inorganic, Bioinorganic, and Organometallic Chemistry Program to support the development and application of high pressure photoacoustic calorimetry. Dr. Theodore J. Burkey of the Chemistry Department, Memphis State University, will construct a cell in which to carry out reactions of organometallic compounds and measure the change in volume due to differences in the volumes of reactants and intermediates or products. The method will be useful in determining detailed reaction mechanisms for photointiated reactions, including substitution reactions and activation of alkanes and other small molecules. The project is viewed as risky since the method may not be sufficiently sensitive. If successful, the method could be useful for studying organometallic reactions, whose mechanisms have not been extensively studied, and for comparison of results with the few other methods used for determining volumes of activation. %%% During the course of reactions, both reactant and solvent molecules rearrange themselves to optimal orientations required for reaction. As a result of this rearrangement, the volume of the reactants changes during the course of the reaction. The volume of the products also differs from that of the reactants. Thus, measurement of volume change during reaction provides information about the energy and steric requirements for reaction. With the support of this award, Dr. Theodore J. Burkey will attempt to develop a new method for measuring volume changes and will gain information on a number of important organometallic reactions, including some catalytic and some light induced processes.
