Electrical conduction through single molecules and self-assembled monolayers

Although research on molecular electronics has drawn increasingly more attention in the last decade, the large spread in obtained results for the conduction rescaled to a single molecule indicates a strong dependence of the measured data on the experimental testbed used. We subdivided a generalized metal-molecule-metal junction into different components and discuss their influence on electrical transport measurements of a single organic molecule or an assembly of molecules. By relating the advantages and disadvantages of different experimental testbeds to the more general view of a molecular junction, we strive to explain the discrepancies between the obtained results on molecular conduction. The reported results on molecular conduction of molecules with an alkane backbone can be categorized into three groups with different resistance values, depending on the device area of the molecular junction and the nature of the contacts. (topical review)