Development of molecules that can switch between redox states with paired and unpaired electrons is important for molecular electronics and spintronics. In this work, a selection of redox-active indenofluorene-extended tetrathiafulvalenes (IF-TTFs) with thioacetate end groups was prepared from a readily obtainable dibromo-functionalized IF-TTF building block using palladium-catalyzed cross-coupling reactions, such as the Suzuki reaction. The end groups served as electrode anchoring groups for single-molecule conductance studies, and the molecules were subjected to mechanically controlled break-junction measurements with gold contacts and to low-bias charge transport measurements in gated three-terminal electromigration junctions. The neutral molecules showed clear conductance signatures, and somewhat surprisingly, we found that a meta–meta anchoring configuration gave a higher conductance than a para–meta configuration. We explain this behavior by “through-space” coupling between the gold electrode and the phenyl on which the anchoring group is attached. Upon charging the molecule in a gated junction, we found reproducibly a Kondo effect (zero-bias conductance) attributed to a net spin. Ready generation of radical cations was supported by cyclic voltammetry measurements, revealing stepwise formation of radical cation and dication species in solution. The first oxidation event was accompanied by association reactions as the appearance of the first oxidation peak was strongly concentration dependent.

We present explicit expressions and the corresponding computer code for all homogeneous space Green's functions for coupled electromagnetic fields and poroelastic waves. The Green's functions are derived from the basic equations in closed-form in wavenumber-frequency and in space-frequency domains. They are given for point sources of any type. This adds several Green's functions to what has been published before. These Green's functions can be used in integral equation formulations, for numerical model validation, and for studying earthquake related electrokinetic effects. The wavenumber domain code for all Green's functions is given with the numerical test on the basic equations to demonstrate correctness. The numerical codes to compute them in space-frequency domain are also given. Numerical inverse FFT routine is used to provide space-time domain results. At seismic frequencies the fast P-wave is radiated with the largest amplitude in all fields, except for the magnetic fields where no P-waves are generated. At ultrasonic frequencies and in the particle and filtration velocity fields generated by an electric current source the slow P-wave has the strongest amplitude. In the filtration velocity and particle velocity the slow P-wave is, respectively, three orders and one order of magnitude stronger than the fast P-wave.

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Abstract-The vector Boundary Element Method (vBEM)is used for the calculation of a matrix that links the tangential components of the current density on the cortical and scalp surface. This so-called transfer matrix is compared t o the transfer matrix that links the potential distribution on both surfaces. Forward and inverse calculations are performed to evaluate both types of transfer matrices.