University of Otago, New Zealand


Te Tari Hua-Ruanuku

Gordon Group Researchers

Sarah Howell
Spectroscopy of Inorganic Complexes

Sarah submitted her PhD in 2005. She is currently a postdoctoral fellow in the UK.

Summary of PhD Research Project

Polypyridyl complexes have a wide range of uses in nanotechnology, photocatalysis and solar cell devices. The key species for use of these complexes in such applications are their reduced state or metal-ligand charge-transfer (MLCT) excited state, in which the metal is formally oxidised and one of the ligands in the complex formally reduced to a radical anion. An increased understanding of these states has the potential to lead to the rational design of materials with desired electronic properties.

We are interested in establishing the structural changes that occur in metal complexes with polypyridyl ligands upon photoexcitation, as this can be related to the excited state lifetimes of these complexes. Cu(I), Ru(II) and Re(I) complexes of 1,10-phenantholine, substituted analogues and deuterated isotopomers are being studied (see below). Techniques employed include: density functional theory calculations, transient resonance Raman spectroscopy, resonance Raman excitation profiles (in collaboration with Prof. D. Philips, University of Hong Kong), spectroelectrochemistry, excited state lifetime measurements (in collaboration with Prof. J. McGarvey, Queen's University of Belfast) and time-resolved infrared spectroscopy (in collaboration with Prof. M. George, University of Nottingham).