Leopold May - Physical, Spectroscopy, History of Chemistry
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Leopold May, Professor Emeritus Physical, B.ChE, 1944, College of the City of New York. M. S., 1949, Ph. D., 1951, Polytechnic Institute of Brooklyn. Exchange Scientist, Academies of USA and USSR, 1976-1977; 1978. Sr. Fulbright Lecturer, 1980 |
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Summary of Research Interests One of the research efforts in our laboratory has been devoted to the interpretation of spectroscopic measurements on a variety of chemical systems including europium, iron, and tin complexes, biochemicals, minerals and alloys. The primary type of spectroscopy used in this research is Mössbauer (or nuclear gamma resonance) spectroscopy, valuable for identifying oxidation and spin states and bonding of metal ions in complexes. Since 1985 with Dr. George Eng of University of the District of Columbia and his group, we have been studying the speciation of tributyltin and triphenyltin compounds in the sediments of the rivers in the vicinity of Washington and the Chesapeake Bay by measuring the Mössbauer spectra of the compounds directly within the sediments. This is now being extended to components of sediments, such as clays. With Dr. Clive I. Wynter of the Nassau Community College and his colleagues, we have doing research on the dynamic structure of europium chelates as well as its fluorescence properties. Another project is the measurement of the ferrous and ferric composition of American Indian Pottery and other ceramic materials. Another research done in conjunction with Dr. John Golin of the Biology Department is concerned with the efflux of drugs from yeast. We have related the efflux of various substrates including tri-n-alkytin chlorides and tetraalkyltins to properties such as molecular volume, hydrophobicity, and distance between the tin and carbon atoms. Unexpectedly, the extent of efflux was not related to the hydrophobicity of the substrate but was related to its surface volume. We have found that there are three sites at which the substrates interact with the Pdr5 depending upon the properties of the substrate. For a recent review of this research, see Golin et al., 2007. Research into the history of chemistry led to the collection of the birthdays of prominent chemists and the listing of significant chemical events, which is used by This Week in Chemical History published by the American Chemical Society. Historical events in spectroscopy may be viewed at Monthly Historical Events in Spectroscopy. Biographies of selected chemists and physicists are found at the History Corner. Also, a listing of historical events in Mössbauer Spectroscopy can be found here. Visit the Hall of Chemical History by viewing the video “Tour of the Hall of Chemical History” prepared by Ms. Adrienne Black, Assistant to the Chairman of the Chemistry Department.
“Effect of E. coli on the speciation of tributyltin compounds in sediments and clays using Mössbauer spectroscopy,” May, L.; Chirdon, T. B.; Song, X.; Zapata, A.; Eng, G., Prepr. Ext. Abstr. ACS Natl. Meet. ACS, Div. Environ. Chem. 2006, 46, 254-257 “Mössbauer Effect of 151Eu in Europium Salen Complex Nanoparticles”, Wynter, C. I.; Brown, D. E.; Iwunzie, M.; Sobel, S. G.; May, L.; Oliver, F. W.; Adeweymo, A. Hyperfine. Int., 2006, 170, 61-66. .“Use of Mössbauer Spectroscopy to Determine the Effect of Salinity on the Speciation of Triorganotins in Anacostia Sediment”, Eng, G., Song, X., and May, L., Hyperfine Int,, 2006, 170, 117-125. “The Yeast Pdr5p Multidrug Transporter: How Does it Recognize So Many Substrates?” Golin, J.; May, L.; Ambudkar, S. V., Biochem. Biophys. Res. Commun., 2007, 356, 1-5. “N. Alkylation of tripodal iron (III) imidazolate complexes. Reactivity and structure”, Brewer, G.; Brewer, C.; Butcher, R. J.; Carpenter, E. E.; May, L.; White, G. , Inorg. Chim. Acta, 2007, 360, 2153-2161. “Synthesis, spectroscopic characterization and X-ray crystal and molecular structures of diphenyltin(IV) complexes of acetone Schiff bases of S-alkyldithiocarcarbzates”, Akbar Ali, M.; Mirza, A. H.; Hamid, M. H. H. A.; Bernhardt, P. V.; Atchade, O.; Song, X.; Eng, G.: May, L., Polyhedron, 2008, 27, 977-984. “The lesser known chemist-composers, past and present,” May, L. Bull. Hist. Chem., 2008, 33, 35-43.
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