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Oligo(para-phenylene-vinylene)-methanethiol of trimer and dimer have been synthesized to prepare monolayers onto Au(111). The trimer diluted in dichloromethane glows with a brilliant blue fluorescence when excited with UV light (365 nm). The absorption and emission spectra of the dimer diluted in CH₂Cl₂ show a blue shift. The molecular level morphologies of the monolayers prepared on gold surfaces were probed by scanning tunneling microscopy or atomic force microscopy (AFM). The dimer is entire trans isomer, which formed highly ordered self-assembled monolayers (SAMs) on Au. The trimer is a mixture of cis–trans isomers, and did not form ordered monolayers on Au. However, the trimer molecules could be embedded in dodecanethiol SAM, and showed higher conductance than oligo(para-phenylene) molecules characterized using a conductive AFM.

In addition to controlling the structure of multi-chromophoric arrays, monitoring the spatial orientation of the chromophores in artificial light harvesting devices is a challenge of growing interest. We report in this article our recent advances in this field. It is expected that a better understanding of the physicochemical properties of rigid cofacial porphyrinic tweezers and an identification of the factors governing them will be crucial for the design and the elaboration of new nano-molecules endowed with original properties. Extended multi-porphyrinic architectures, polypeptides bearing pendant porphyrins have been synthesized as linear devices, and a star-like pentaporphyrin as an arborescent array. The structure and the original conformation of the latter confer to this system an unusual duality in its physicochemical properties.

A novel unsymmetrically substituted hydroxy-functionalized Zn(II) phthalocyanine (Pc) 1, bearing long aliphatic chains, namely, dodecyloxy units, has been designed and synthesized to investigate the influence of the terminal hydroxyl group on the formation of self-assembled nanostructures. The symmetric derivative, octadodecyloxy-Zn(II)Pc (2) has been also synthesized and used as reference compound for comparison purposes. The supramolecular organization of the Pcs has been carried out by spin-coating on a highly ordered pyrolytic graphite (HOPG) surface and has been investigated by atomic force microscopy (AFM) and scanning electron microscopy (STM). AFM and STM studies showed that unsymmetrically substituted hydroxy-functionalized Zn(II)Pc1 gives rise to the formation of wire-like structures in different lengths from nanometer to micrometer scales, whereas in the case of the symmetrical Zn(II)Pc2 the formation of the wires on HOPG was less pronounced.

In the face of the fact that the development of traditional silicon-based electronic devices is increasingly limited, single molecule electronic device, which has been attracting more and more attention, is considered as one of the most hopeful candidates to realize the miniaturization of conventional electronic devices. In this paper, an overview of single molecule electronic devices is provided, including molecular electronic devices and electrode types. First, several molecular electronic devices are presented, including molecular diodes, molecular memories, molecular wires, molecular field effect transistors (FET) and molecular switches. Then the influence of different electrode types of the transport characteristics is introduced, showing that graphene is a promising electrode material for single molecule electronic devices. Moreover, other excellent characteristics of molecular devices are briefly introduced, such as potential thermoelectric effects, new thermally induced spin transport phenomena and negative differential resistance (NDR) behavior. Finally, the future challenges to the development of electronic devices based on single molecules are described.