Boz, Serpil. Controlling intermolecular interactions at surfaces through chemical ligands : supramolecular aggregation, covalent coupling and chirality at reduced dimensions. 2010, PhD Thesis, University of Basel, Faculty of Science.
Official URL: http://edoc.unibas.ch/diss/DissB_9148
By making use of a new concept, we are able to control both, the molecular self-assembly and the subsequent intermolecular coupling reactivity by protecting group chemistry. We describe heat induced formation of polymeric structures from biphenyl derivatives adsorbed on both Cu(111) and Ag(111) surfaces. Moreover, we studied how to control the arrangement and the size of the resulting polymeric structures by modification of the end groups of the biphenyl units.
For all biphenyl derivatives, well-ordered supramolecular networks are transformed into covalently bound dimers through annealing at elevated temperatures. Further annealing of such structures results in the formation of interlinked cross-like or trimeric structures and long chains.
In the second part, the effect of the chirality on the resulting surface assemblies is studied for the case of a helicene derivative deposited on a Cu(111) surface. The helicene derivative used in this work consists of a helicene core to which two opposed cyano side groups are attached. Herein, it is shown how the cyano groups influence the adsorption geometry of the molecules upon deposition on the surface and the formation of the self-assembled structures.
Adsorption of both racemic and enantiopure forms of the molecule are analyzed in detail and a chirality transfer of the molecular building blocks into the extended molecular domains is confirmed from the comparison of the experimental results of both cases. Finally, behaviour of the enantiopure form of the molecule at room temperature is studied, which reveals a metastable nanoporous network. In this section, a time induced phase transition of the nanoporous network into a stable dimeric arrangement is shown and possible reasons for this conversion are discussed.
|Committee Members:||Jung, Thomas Andreas and Mayor, Marcel|
|Faculties and Departments:||05 Faculty of Science > Departement Physik|
|Bibsysno:||Link to catalogue|
|Number of Pages:||121 S.|
|Last Modified:||30 Jun 2016 10:41|
|Deposited On:||24 Sep 2010 07:11|
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