Timothy L. Kelly

Background

B.Sc. (Hons.) expected May 2005, Memorial University, NL, CA

Publications

1. Hilde Grove, Timothy L. Kelly, Laurence K. Thompson, Liang Zhao, Zhiqiang Xu, Tareque S. M. Abedin, David O. Miller, Andres E. Goeta, Claire Wilson, and Judith A. K. Howard. Copper(II) complexes of a Series of Alkoxy Diazine Ligands: Mononuclear, Dinuclear, and Tetranuclear Examples with Structural, Magnetic, and DFT Studies. Inorg. Chem., 43, 4278 (2004).

2. Liang Zhao, Zhiqiang Xu, Hilde Grove, Victoria A. Milway, Louise N. Dawe, Tareque S. M. Abedin, Laurence K. Thompson, Timothy L. Kelly, Rosemary G. Harvey, David O. Miller, Laura Weeks, Joseph G. Shapter, and Kenneth J. Pope. Supramolecular Mn(II) and Mn(II)/Mn(III) Grid Complexes with [M9(m2-O)12] Core Structures. Structural, Magnetic, and Redox Properties and Surface Studies. Inorg. Chem., 43, 3812 (2004).

3. Zhiqiang Xu, Laurence K. Thompson, Victoria A. Milway, Liang Zhao, Timothy Kelly, and David O. Miller. Self-Assembled Dinuclear, Trinuclear, Tetranuclear, Pentanuclear, and Octanuclear Ni(II) Complexes of a Series of Polytopic Diazine Based Ligands: Structural and Magnetic Properties. Inorg. Chem., 42, 2950 (2003).

Research Interests and Current projects

Honours 490A Project: Metal Complexes of a Fused Aromatic Diazine-based Ligand
I have been synthesizing transition metal complexes of tetranucleating ligands based on a benzobispyridazine backbone. The ligand has four, bidentate chelation sites, serving to bind two pairs of metal ions in close proximity. These heteroleptic systems have been synthesized with a variety of auxiliary ligands, leading to a number of different bridging arrangements. Of particular note is the fact that the small differences in structure brought about by varying the nature of the bridge lead to interesting variations in magnetic properties. Both antiferromagnetic and ferromagnetic coupling has been observed with these complexes. Additionally, the polycyclic aromatic nature of the ligand backbone is a potential site for radical generation. With this in mind, both experimental and theoretical studies have been carried out in order to assess the stability of the anionic radical formed by a one-electron reduction.

Spectroelectrochemistry and Electron Dynamics
Mn[3x3] grid systems have shown a rich electrochemical response in the anodic region, with oxidation events occuring throughout the grid framework. These Mn(II)/Mn(III) redox couples can be exploited to synthesize (both electrochemically and chemically) mixed-valent manganese grids. These show very interesting UV/Vis/NIR spectra, which include the development of inter-valence charge transfer (IVCT), and ligand-to-metal charge transfer (LMCT) bands. The IVCT bands have been analyzed using standard Marcus-Hush theory. This project relies heavily on techniques such as cyclic voltammetry, differential pulse voltammetry, coulometry, and UV/Vis/NIR spectrometry, including a coupled coulometry/spectrometry cell.

Quantum Chemistry of Transition Metal Complexes
Density functional theory has proven to be an effective quantum chemical technique in the study of inorganic complexes, balancing the need to include correlation effects against computational expense. The study of magnetic-exchange coupling in spin-coupled transition metal clusters has been made possible by the advent of broken-symmetry DFT techniques. This technique has been successfully employed within the group to obtain theoretical estimates of 2J values. As well, nickel(II)-catalyzed hydrolysis pathways have been mapped out using the popular B3LYP hybrid functional.