Organic Dynamics in Crystalline Solids: Chemistry Near Zero Kelvin

University Of California-Los Angeles, Los Angeles CA

Investigators

Abstract

With this renewal award the Organic and Macromolecular Chemistry Program continues support for the work of Dr. Miguel A. Garcia-Garibay in the Department of Chemistry and Biochemistry at the University of California, Los Angeles. The research aims at understanding chemical dynamics in highly constrained environments - crystalline organic solids at temperatures approaching absolute zero. Reactions are initiated by laser flash photolysis and studied by a variety of methods including x-ray diffraction, differential scanning calorimetry, solid state 13C NMR, and infrared and Raman spectroscopy. Quantum mechanical tunneling will be studied by means of deuterium isotope effects, anomalous Arrhenius plots of rate constants, and by theoretical and computational chemistry. The proposed work involves the changes in reactivity of highly reactive organic intermediates, generated photochemically, when these intermediates are formed not in liquid solution where there is considerable freedom of motion, but in highly constrained crystalline solids at low temperatures. Unusual products can form under these circumstances at rates that are much higher than would be expected based on rates near room temperature. Studies of this type can give insight into the detailed dynamics of the reactions involved. The work provides excellent training for students in organic synthesis, spectroscopy, kinetics, and computational chemistry. The PI actively recruits underrepresented minority students, especially Hispanics, to do research in his laboratory.