Polymer two-dimensional networks of Au55 clusters

Monolayers and thin films of Au-55 clusters, linked by different dithiol spacer molecules and by polymerization between functionalized ligands, were prepared and investigated by TEM and AFM. Due to spacer molecules of different lengths, the cluster-cluster distances could be varied from 1.3 up to 3.8 nm, enabling later investigations of electron transport processes in two dimensions. Film formation was carried out using either Langmuir-Blodgett techniques or spin-coating processes in the presence of the spacer molecules. Polymerization reactions between neighboured clusters in monolayers or thin films succeeded by the use of vinyl-substituted ligand molecules. (Vinyl)(8)Si8O11(OH)(2) and p-styryl-diphenylphosphine modified Au-55 clusters could be linked by light-induced polymerization via the vinyl functions.