Transition metal terpyridine complexes for molecular electronics

Chappell, Sarah Transition metal terpyridine complexes for molecular electronics. PhD thesis, University of Liverpool.

Text chappellsar_oct2014_2011084.pdf - Unspecified Available under License Creative Commons Attribution. Download (5MB)

Abstract

Currently there is a huge amount of interest in the synthesis and electrical characterisation of single molecules that have the potential for use in electronic devices. In order for this technology to move forward it is necessary to gain insights into structure-property relationships at the nanoscale, as well as a basic understanding of the charge transport through various molecular architectures. It has previously been demonstrated that the electrical properties of redox active single molecules can be investigated as a function of potential. This thesis investigates the single molecule conductance properties of molecules incorporating a transition metal centre. The research presented in this thesis investigates two major studies. The first is a study into the electrochemical and conductance properties of a variety of transition metal based complexes. Initial electrochemical and conductance investigations of a series of pyterpy transition metal complexes showed a similar conductance for all the series, this was investigated in two different environments. The ligand was then varied and several ruthenium complexes were investigated, to investigate the anchoring group effect and to examine the length and conductance relationship. The data presented here demonstrates a higher conductance for methyl sulphide anchoring group than the pyridyl anchoring group. The data presented showed a low dependence on molecular length, suggesting a hopping transport mechanism. The conductance behaviour of two [M(pyterpy)2](PF6)2 complexes were investigated as a function of potential in an ionic liquid medium. The data presented exhibited an increase in conductance as the redox potential was reached. The second study investigated the conductance behaviour of two 6-porphyrin nanorings. This is the first conductance study on these porphyrin based complexes. The study investigated a ‘complete’ and ‘broken’ nanoring and showed a smaller than expected difference in conductance between them. This preliminary study has allowed for the development of the structure to investigate possible quantum interference effects.

Item Type:	Thesis (PhD)
Additional Information:	Date: 2014-10-31 (completed)
Subjects:	?? QD ??
Depositing User:	Symplectic Admin
Date Deposited:	03 Aug 2015 10:01
Last Modified:	17 Dec 2022 01:27
DOI:	10.17638/02011084
URI:	https://livrepository.liverpool.ac.uk/id/eprint/2011084