SUE B. CLARK, PhD is the Westinghouse Distinguished Professor of Chemistry with tenure at Washington State University in Pullman, Washington. She is presenting this lecture which honors Prof. Richard W. Fink, a former professor in the School of Chemistry and Biochemistry. The lecture is on October 28, 2008 at 3:00 PM, G011 Molecular Science & Engineering Building (MS&E).

Uranium Coordination Chemistry: Mineral Phases, Solid Solutions, and Transuranium Partitioning

Natural uranium occurs as various mineral forms that reveal fascinating coordination chemistries and surface reactivities. The hexavalent uranium minerals are the most prevalent in oxidizing environments, and many of the U(VI) minerals, such as uranophane (depicted below), are layered structures that behave much like clay minerals. As such, they can serve as solids to which the transuranic elements are incorporated and/or sorbed. Analogies can be made with U mineral deposits, where the assemblage of crystalline U(VI) solids act as hosts for the natural decay products of primordial U. In this presentation, the thermodynamics and mechanism(s) of fission products and transuranic actinide incorporation into U(VI) silicate solids will be discussed. In addition, colloidal behavior and sorption mechanisms will also be described.

Dr. Clark's current research areas include the environmental chemistry of plutonium and other actinides, chemistry of high level radioactive waste systems, and actinide separations. Her research efforts are supported by grants from the National Science Foundation, the U.S. Nuclear Regulatory Commission, and the U.S. Department of Energy's Office of Science, Office of Environmental Management, Office of Nuclear Energy, and National Nuclear Security Administration. She currently serves on the National Research Council's Nuclear and Radiation Studies Board, the Basic Energy Sciences Advisory Committee for the U.S. DOE, and is a consultant to Battelle Memorial Institute and the Helmholtz Association of German Research Centers, She holds a BS degree in Chemistry from Lander College (Greenwood, SC) and MS and PhD degrees in Chemistry from Florida State University (Tallahassee, FL). Prior to joining Washington State University in 1996, she was an Assistant Research Ecologist at the University of Georgia's Savannah River Ecology Laboratory (1992-1996), and Senior Scientist at Westinghouse Savannah River Company's Savannah River Technology Center (1989-1992).

Richard W. Fink was born on January 13, 1928 in Detroit, Michigan. As a youngster, Dick demonstrated an interest in science, often alarming the neighbors when his "experiments" generated smoke and foul odors from his basement "laboratory". Dick obtained a Bachelor's degree in Chemistry from the University of Michigan in 1948, followed by a Master's from the University of California, Berkeley in 1949, under the direction of Glenn T. Seaborg. He obtained his Ph.D. in Nuclear Chemistry from the University of Rochester in 1953. Dick spent his early years in academia at the University of Arkansas and in 1963 was the recipient of a Fulbright Faculty Fellowship. He spent the year pursuing research in Germany. During this period, Dick was approached by William M. Spicer with an offer to come to Georgia Tech, joining the faculty in the School of Chemistry in 1965. While at Georgia Tech, Dick had the distinction of having twenty-four years of continuous research support from the Department of Energy and its predecessors the Atomic Energy Commission and ERDA. He was one of the founding members of the University Isotope Separator project at the Oak Ridge National Laboratory in the mid 1970s. Dick has over 150 publications in refereed scientific journals and one particular paper on "X-ray Fluorescence Yields" has been cited over 1400 times in the scientific literature. During his time at Tech, he was mentor to seventeen post-doctoral fellows and research scientists and was thesis advisor to twenty Ph.D. and M.S. students, a significant number of whom went on to academic careers. Dick was an accomplished horseman and a lover of chocolate.