- Chris Larsen
- Supervisor: Dr Nigel T. Lucas
- Tel: (03) 479 9089
- Location: Science II, 3c3
Chris graduated his PhD in May 2016 and is currently a Swiss Government Excellence Postdoctoral Scholarship holder at the University of Basel, Switzerland.
Electron donor-acceptor (D-A) materials are a class of optically-active compounds, widely utilised in dye-sensitised solar cells, organic photovoltaics, organic light-emitting diodes, nonlinear optical devices, biological probes and as therapeutic agents. Despite their use in such a wide range of applications, many fundamental properties of D-A materials are still poorly understood.
This research investigated several previously unexplored aspects of the interaction between donor and acceptor and their influence on the electronic and photophysical properties of the materials, utilising polypyridyl acceptors with increasing levels of spectroscopic complexity: benzo[c][1,2,5]thiadiazole (btd), dipyrido[3,2 a:2ʹ,3ʹ c]phenazine (dppz) and 5,6,11,12,17,18-hexaazatripnaphthalene (hatn). The aspects of the D-A interaction investigated in this thesis are energetics, connectivity and additivity. Re(I) tricarbonyl complexes of the dppz ligands provide competing MLCT processes, the influence of which can be spectroscopically determined and used to characterise the strength of the interaction between donor and acceptor.
Specifically, energetics was investigated through tuning of the triarylamine (TAA) donor through peripheral substitution with electron-donating methoxy and electron-withdrawing cyano groups, connectivity was investigated in three ways: (1) as a function of the D-A distance, using linear, conjugated bridging units with minimal electronic influence – namely, the para-phenylenes and para-ethynylphenylene; (2) as a function of the D-A torsion angle, through incorporation of electronically inert steric factors on either the donor or acceptor that restrict the D-A conformation; (3) as a function of the electronic influence of the bridging unit, using the conducting thienyl and insulating triazolyl bridges. Additivity was investigated through incorporation of varying numbers of donors around a hatn acceptor.
- Benzo[c][1,2,5]thiadiazole Donor-Acceptor Dyes: A Synthetic, Spectroscopic and Computational Study. Jonathan E. Barnsley, Georgina E. Shillito, Christopher B. Larsen, Holly van der Salm, Lei E. Wang, Nigel T. Lucas and Keith C. Gordon, J. Phys. Chem. A, 2016, 120, 1853-1866.
- Effects of Protonation on the Optical and Photophysical Properties of [ReCl(CO)3(dppz-TAA)] and [Ru(bpy)2(dppz-TAA)]2+. Holly van der Salm, Christopher B. Larsen, James R. W. McLay, Gregory S. Huff, Keith C. Gordon, Inorg. Chim. Acta. 2015, 428, 1-7.
- Site Selectivity of [RuCp*]+ Complexation in Cyclopenta[def]triphenylenes. Bryce R. Hoggard, Christopher B. Larsen and Nigel T. Lucas, Organometallics, 2014, 33, 6200-6209.
- Stretching the phenazine MO in dppz: the effect of phenyl and phenyl-ethynyl groups on the photophysics of Re(I) complexes. Holly van der Salm, Christopher B. Larsen, James R. W. McLay, Michael G. Fraser, Nigel T. Lucas and Keith C. Gordon, Dalton Trans. 2014, 43, 17775-17785.
- Intraligand Charge-Transfer Excited States in Re(I) Complexes with Donor Substituted Dipyridophenazine Ligands. Christopher B. Larsen, Holly van der Salm, Charlotte A. Clark, Anastasia B. Elliott, Michael G. Fraser, Raphael Horvath, Nigel T. Lucas, Xue Zhong Sun, Michael W. George and Keith C. Gordon, Inorg. Chem. 2014, 53, 1339-1354.