Gellert Mezei

Assistant Professor
gellert.mezei@wmich.edu

Inorganic and coordination chemistry, ligand design and synthesis, supramolecular architectures, topological molecules, advanced materials

1997: B.S. Babes-Bolyai University, Romania
1998: M.S. Babes-Bolyai University, Romania
2004: Ph.D. University of Puerto Rico
2004-2007: Postdoctoral Fellow, University of Michigan

RESEARCH FOCUS

Functional Supramolecular Architectures
Rotaxanes and catenanes – supramolecules that contain mechanically interlocked components – are the focus of increased attention in recent years due to their potential for being developed into molecular devices and machines. Examples of such rotaxane- or catenane-based devices include molecular shuttles, elevators, muscles, nanovalves, information storage devices and components for molecular electronics such as molecular switches and single-molecule transistors. We are interested in engineering more complex molecular machinery by assembling two or more such devices into discrete supramolecular entities. We are also pursuing the incorporation of rotaxanes into 3-dimensional architectures in order to prepare functional materials with controllable pore sizes and shapes.

Topologically Unusual Molecules
Knotted and interlinked molecules (for example, the molecular analogs of the trefoil knot and the Borromean rings) are an interesting but poorly-studied class of topological molecules. While it is known that biological systems containing DNA and proteins are capable of adopting very complex knotted structures and forming networks of thousands of topologically interlocked circles, only a few and the simplest of such molecules have been synthesized to date. By using inorganic templates, we work on expanding the inventory and the knowledge of new topological molecules, the pentafoil knot and the triply interlocked [2]catenane being the first two targets.

Molecularly Woven Materials
Strength, lightness and non-brittleness are crucial features of some materials used in everyday life. For certain specialized applications, extreme strength is required while lightness and non-brittleness are still desirable. The challenge to combine all these properties into one material is not trivial, since very tough materials are usually heavy and/or brittle. By analogy to macroscopic woven materials, such as textiles and ropes, we believe that materials woven at the molecular level should be the ultimate choice featuring extreme strength while being lightweight and non-brittle. In creating these novel materials, we exploit coordination chemistry and ligand design, using building blocks with intertwined strands that are subsequently “sewn” together on the molecular level.

 Students in my group are engaged in many areas including synthesis and characterization of organic ligands and coordination compounds, NMR, UV-vis and IR spectroscopy, single crystal X-ray diffraction, mass spectrometry, surface analysis and mechanical characterization.

Selected Publications

1.      G. Mezei, C. M. Zaleski, V. L. Pecoraro, “Structural and Functional Evolution of Metallacrowns”, Chem. Rev. 2007, 107, 4933.

2.      G. Mezei, J. W. Kampf, V. L. Pecoraro, “Metallacrown-based Compartments: Selective Encapsulation of Three Isonicotinate Ions in Non-Centrosymmetric Solids”, Chem. Commun. 2007, 1148.

3.      G. Mezei, J. W. Kampf, V. L. Pecoraro, “Temperature-, molar ratio- and counterion-effect on the crystal growth of bipyridinium-bis-alkylcarboxylic acid/crown ether pseudorotaxanes”, New J. Chem. 2007, 31, 439.

4.      G. Mezei, M. Rivera-Carrillo, R. G. Raptis, “Trigonal Prismatic CuII6-Pyrazolato Cages: Structural and Electrochemical Study, Evidence of Charge-Delocalisation”, Dalton Trans. 2007, 37.

5.      G. Mezei, R. G. Raptis, J. Telser, “Trinuclear, Antiferromagnetically-Coupled CuII Complex with an EPR Spectrum of Mononuclear CuII: Effect of Alcoholic Solvents”, Inorg. Chem. 2006, 45, 8841.

6.      G. Mezei, J. E. McGrady, R. G. Raptis, “First Structural Characterization of a Delocalized, Mixed-Valent, Triangular Cu37+ Species: Chemical and Electrochemical Oxidation of a CuII3(μ3-O) Pyrazolate and Electronic Structure of the Oxidation Product”, Inorg. Chem. 2005, 44, 7271.

7.      G. Mezei, P. Baran, R. G. Raptis: “Anion Encapsulation by Neutral Supramolecular Assemblies of Cyclic CuII-Complexes: a Series of Five Polymerization Isomers, [{cis-CuII(µ-OH)(µ-pz)}n], n = 6, 8, 9, 12 and 14”, Angew. Chem. Int. Ed. 2004, 43, 573.

8.      G. Mezei, R. G. Raptis, “Pyrazole-4-Sulphonate Networks of Alkali and Alkaline-Earth Metals. Effect of Cation Size, Charge, H-Bonding and Aromatic Interactions on the Three-Dimensional Supramolecular Architecture”, New J. Chem. 2003, 27, 1399.