Because of their spectroscopic and chemical properties, the lanthanide(III) ions have been important spectroscopic probes for calcium and magnesium binding studies in biological systems. For example, Eu(III) luminescence studies have become an important measure of the number of interacting atoms and water molecules between a biochemical material and the metal ion domain. However, despite over twenty years of their applications in biological systems, much fundamental information about the interactions of these lanthanide ions with their surroundings is still unknown. We propose using spectroscopic techniques, including ultrasonic absorption, FT-NMR, FT-IR and UV-vis methods, to develop information about the composition of the inner coordination shell of these cations. A second aspect of this proposal is the study of d-transition ions, cobalt, nickel, copper and zinc, in water and mixed solvents to learn about the domains surrounding the metal ion centers. Specific studies include: (1) Ultrasonic absorption of Yb(III) with sulfate, La(III) with 18-crown-6, and Zn(II) with glycine and possibly carbonic anhydrase or carboxypeptidase A. (2) Equilibrium constant determinations of Co(II) with Cl- and with glycine, Ni(II) and Cu(II) with SCN-, and Cu(II) with sulfate. (3) Structural studies of solvated LaCl/3 in aqueous organic solvents using FT-NMR and FT-IR at low temperatures to determine the composition of the inner coordination shell. (4) FT-NMR studies of zinc complexes in mixed solvents to detect geometry changes in solution. (5) We intend to initiate comparisons between the lanthanides and the actinide elements towards future work on biological and environmental concerns about actinide contamination. (6) We will investigate complex formation between the buckminsterfullerenes and organic donor/acceptor molecules.
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