Synthesis of a vinylogue tetrathiafulvalene derivative and study of its charge transfer complex with TCNQF4

Efficient synthesis of a vinylogue TTF derivative bearing four cyanoethylsulfanyl substituents, 9 is described. Cyclic voltammetry establishes that the novel compound shows good donor properties and a reduced on-site coulombic repulsion. Single crystal X-ray structure determination shows that the molecule has a planar structure of the conjugated moiety with a slipped π−π stacking organization in the crystal parallel to the crystallographic a axis. EPR, UV–vis and IR spectroscopies show that 9 forms a charge transfer complex with TCNQF4. EPR studies allow for the recognition of the 3:2 stoichiometry ratio between donor and acceptor while IR spectroscopy gave the estimation of the ionicity of the complex, which was found to be 0.31

Single-crystal organic field-effect transistors based on dibenzo-tetrathiafulvalene

We report on the fabrication and characterization of field-effect transistors based on single crystals of the organic semiconductor dibenzo-tetrathiafulvalene (DB-TTF). We demonstrate that it is possible to prepare very-good-quality DB-TTF crystals from solution. These devices show high field-effect mobilities typically in the range 0.1–1?cm2/V?s. The temperature dependence was also studied revealing an initial increase of the mobility when lowering the temperature until it reached a maximum, after which the mobility decreased following a thermally activated behavior with activation energies between 50 and 60?meV. Calculations of the molecular reorganization energy and intermolecular transfer integrals for this material were also performed and are in agreement with the high mobility observed in this material.Kavli Institute of NanoscienceApplied Science

A quaterthiophene-based rotaxane: synthesis, spectroscopy, and self-assembly at surfaces.

Threaded molecular wires are shown to feature tunable properties. A new rotaxane based on a quaterthiophene threaded through a single β-cyclodextrin exhibits delocalization of the aromatic system that is also extended onto the central phenyl rings of the m-terphenylene end-groups. The rotaxane can undergo self-assembly that is better than the analogous bithiophene derivative, due to the increased π-π interactions

Chemical control over the energy-level alignment in a two-terminal junction

10.1038/ncomms12066Nature Communications71206

Fluid Mixing for Low-Power \u2018Digital Microfluidics\u2019 Using Electroactive Molecular Monolayers

A switchable electrode, which relies on an indium-tin oxide conductive substrate coated with a self-assembled monolayer terminated with an anthraquinone group (AQ), is reported as an electrowetting system. AQ electrochemical features confer the capability of yielding a significant modulation of surface wettability as high as 26\ub0 when its redox state is switched. Hence, an array of planar electrodes for droplets actuation is fabricated and integrated in a microfluidic device to perform mixing and dispensing on sub-nanoliter scale. Vehiculation of cells across microfluidic compartments is made possible by taking full advantage of surface electrowetting in culture mediu