| Abstract
| - Trans-4-methyl-4‘-(−S−(CH2)n−O−)azobenzenes (1) with varying alkyl chain lengths (n= 4, 6, 9, 12) and trans-4-methyl-4‘-(−S−(CH2)n−O−)stilbenes (2) (n = 6, 7, 8, 9) were usedto cap colloidal gold clusters, yielding composite shell−core nanostructures 3 and 4,respectively. Aggregation of the terminal arene moieties by π-stacking within the organicshells was weak in these composite particles. Upon irradiation at 350 nm, photoisomerizationof the appended trans isomer to the corresponding cis isomer takes place both in solutionand in the composite cluster. Inefficient photodimerization could be observed by 1H NMRspectroscopy for cluster 4. The quantum yields for photoisomerization of the compositeclusters 3 and 4 were affected by the length of the linker because of distance-dependentthrough-bond quenching by the metal core.
|
