The binding of liquid crystal molecules to surfaces in liquid crystal cells is a difficult interaction to characterise as the environment which surrounds the liquid crystal molecules makes the systems inaccessible to experimental and theoretical studies. However, insight may be gained from an examination of simplified systems which represent specific aspects of this interaction. First principles electronic structures calculations based on planewave density functional theory allow the adsorption of an isolated molecule on an extended surface to be examined and compared with studies on complex molecules. One possible binding interaction between a liquid crystal molecule and a metallic surface may be represented by the interaction of a conjugated p system with a metal. In order to characterise this interaction, this thesis examines the interaction of ethylene with aluminium and copper, and benzene with copper. The electronic interaction which occurs between the species can be rationalised by an identification of criteria which are important for the formation of a chemical bond in a complex molecule and an examination of whether these criteria can be met on adsorption of the hydrocarbon on an extended surface. It is found that ethylene is physisorbed on the s-p metal aluminium surface, but can be chemisorbed on the transition metal copper surface. Benzene can also be chemisorbed on a copper surface at certain sties. These results are explained by an examination of the Al(C<sub>2</sub>H<sub>4</sub>), Cu(C<sub>2</sub>H<sub>4</sub>) and Cu(C<sub>6</sub>H<sub>6</sub>) complexes.
| Identifer | oai:union.ndltd.org:bl.uk/oai:ethos.bl.uk:653424 |
| Date | January 2001 |
| Creators | King, Elizabeth Margaret |
| Publisher | University of Edinburgh |
| Source Sets | Ethos UK |
| Detected Language | English |
| Type | Electronic Thesis or Dissertation |
| Source | http://hdl.handle.net/1842/15166 |
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