Department of Chemistry


 High-nuclearity transition metal and lanthanide clusters

One of our research interests is focused on the synthesis, structural (through single-crystal X-ray crystallography), and spectroscopic and physicochemical characterization of new polynuclear 3d- and 4f-metal complexes (both cage-like and single-strand wheels) bearing various inorganic and/or organic bridging ligands. This is a modern subfield of Synthetic Inorganic Chemistry and Coordination Chemistry, currently called “Molecular Nanoscience”, and provides a ‘bottom-up’ approach to the nanoscale.
High-spin molecules, single-molecule magnets and single-chain magnets
One of the most attractive challenges in the field of Molecular Magnetism, and simultaneously one of the current research interests in Stamatatos’ group, is the synthesis and magnetochemical characterization of new high-spin molecules, single-molecule magnets (SMMs) and single-chain magnets (SCMs) through a targeted conversion of non-SMM species into SMMs without changing the identity of core bridging atoms or the electron count, but instead by introducing a ligand-induced structural perturbation of the magnetic core. SMMs could find use in potential applications such as high-density information storage, quantum computing and spin-based molecular electronics, while high-spin, but non-SMM, molecules are beneficial for low temperature magnetic cooling, providing a potential for replacement of the current low temperature refrigerant, helium-3, which is both expensive and very rare.
Towards multifunctional molecular materials displaying magnetic and optical properties
The current interest of many research groups worldwide is focused on the synthesis of multifunctional (or “hybrid”) molecular materials, which are species exhibiting more than one physical properties within the same molecule or family of isomorphous compounds. Towards this aim, polynuclear lanthanide complexes (4f-metal clusters) appear as promising candidates, given their contributions to various research areas, such as molecular magnetism, optics, catalysis and medicine. This is an issue of vital importance in the field of molecular electronics.
Bioinorganic Chemistry: Towards models of the oxygen-evolving complex (OEC) of photosystem II
Among the various reasons for the current intense interest in manganese chemistry is the existence of this metal at the active sites of several redox enzymes, the most important of which is the oxygen-evolving complex (OEC) on the donor side of photosystem II (PS II) in green plants, algae and cyanobacteria. The OEC catalyses the oxidation of H2O to molecular dioxygen through a four-electron process, and is the source of essentially all the O2 on this planet. The OEC has long been known to contain four Mn and one Ca2+ ions, with the former atoms in a high oxidation state level. Our group is focused on the synthesis and detailed study of synthetic analogues (molecular models) of this {Mn4Ca} cluster which would greatly enhance our understanding of the spectroscopic, physical and catalytical properties of the WOC, as well as its reactivity and functional characteristics.

Dept. of Chemistry
Brock University
1812 Sir Isaac Brock Way
St. Catharines, ON
Canada, L2S 3A1
Tel: (905) 688-5550 x3406

Administrative Assistant:
Marie Harris

Razvan Simionescu