Molecular Electronic Devices Based on Oligothiophene Architecture
Simon Dunne*, Lasse Nurkkala, and Robert Steen
Institutionen för Biologi och Kemiteknik, Mälardalens Högskola,
Eskilstuna 63105 Sweden
This is an abstract
for a presentation given at the
Foresight Conference on Molecular Nanotechnology
To meet the demands of high computing speed and almost infinite memory storage capacity, future generations of computers may well be assembled from molecules rather than silicon/metal/insulator constructs. 'Molecular electronics' is already an established field of cross-disciplinary research combining chemistry, physics, and material science with electronics. Devices such as transistors, rectifiers, wires, switches and memory units have already been demonstrated, but a fully functional molecular circuit remains elusive. The size of such devices is of the order of nanometers, making them suitable for the interaction with cellular systems and macroscopic electronic elements. However this is a molecular size range that is intermediate between that of the organic chemist and that of the polymer chemist, and hence little is known about the behaviour and properties of such macromolecules.
Our research is focused upon the construction of molecular electronic devices based upon the coupled metal complexes. The coupling of oligothiophene systems via purpose-built bi- and ter-pyridine connectors to metal complexes allows the construction of devices in which the electron flow can be controlled through both steric and electronic factors. This lattice of lipophilic molecular wires with charged metal complex junctions thereby creates molecular networks with unique composite character. To be able to demonstrate that such materials are viable, robust and functional and that they can be interfaced with existing technology will represent a major breakthrough in the development of smart materials.
To this presentation we shall discuss our results on the development of (i) synthetic methodology for the efficient and large-scale generation of solubilised oligothiophene building blocks; (ii) a number of molecular switch prototypes have been developed and are currently under test as both interrupt and network control devices (iii) assembly methodology which ensures selective (and asymmetric) coordination; (iv) new methods for the introduction of polarising substituents onto 2,2'-bipyridine connectors and for the generation of fused thienobipyridine systems.
While much current molecular electronics research is focussed upon using nanomolecules to straddle tiny bimetallic gaps, this project goes a step beyond introducing several metallic junction points into an organic matrix. This may allow a higher level of addressability with the possibility of chemical, electrical or photochemical switching between 'binary' states.
Institutionen för Biologi och Kemiteknik,
Gamla Tullgatan 2
Eskilstuna 63105 Sweden
Phone: +46 16 153428 Fax: +46 16 153710