electrochemical behavior of the new mono and dinuclear co (iii)  complexes of  the types trans-[pyco((do)(doh)pn )(l)]pf6   and [{py co((do)(doh)pn)}2 (μ-dicyd)] (pf6)2   have been studied in acetonitrile solution.  all the  mono nuclear complexes  show two quasi- reversible reduction couples associate  to co(iii/ii)and  co(ii/i). each of these redox couples split to two  one electron  waves in...

Melanins are pigmentary macromolecules found throughout the biosphere that, in the 1970s, were discovered to conduct electricity and display bistable switching. Since then, it has been widely believed that melanins are naturally occurring amorphous organic semiconductors. Here, we report electrical conductivity, muon spin relaxation, and electron paramagnetic resonance measurements of melanin a...

The redox potentials for successive oxidations in a series of ligand-bridged dinuclear ruthenium complexes are shown to be dependent on the identity of the anion used as the electrolyte in the electrochemical measurements. Since the differences between these redox potentials (DeltaE(ox)) are often used to calculate the comproportionation equilibrium constants (K(c)) in mixed-valence species--an...

Nickel catalysis: Nickel-catalyzed cross-coupling reactions have become a powerful methodology to construct C-heteroatom bonds but often require non-equimolar amounts of coupling partners. In this study we reveal the competition between productive catalysis and deleterious pathways (comproportionation protodehalogenation) in commonly proposed self-sustained NiI/NiIII catalytic cycle. Thereby sh...

Complexes of the type {[(pyS)Ru(NH(3))(4)](2)-μ-L}(n), where pyS = 4-mercaptopyridine, L = 4,4'-dithiodipyridine (pySSpy), pyrazine (pz) and 1,4-dicyanobenzene (DCB), and n = +4 and +5 for fully reduced and mixed-valence complexes, respectively, were synthesized and characterized. Electrochemical data showed that there is electron communication between the metal centers with comproportionation ...

Multiple synthetic pathways were explored for the preparation of ethynylarene-containing ferrocenylene macrocyles. Accordingly, synthesis novel bis- and tris-ferrocenylene macrocycles, containing a diethynylpyridine bridging group was achieved, evidence is also provided number linear-analogues formed as by-products. The electrochemical properties macrocycles examined, it shown that observable r...

The key property of Frost diagram has been confirmed using thermodynamic and linear algebra methods. On the basis of the thermodynamic data, the areas of thermodynamic stability of ruthenium species of different valence states as a function of pH for each degree of oxidation have been determined. Subsequently, based on the diagrams calculated for several values of pH, a narrow ΔpH value is dete...

Electrocatalytic behavior of TEMPO derivative SAMs on gold has been studied in the presence of benzyl alcohol. The results demonstrate that interfacial activity of the SAMs can be enhanced by diluting the TEMPO moiety with an alkyl passive matrix. The absolute catalytic activity exhibits a maximum for an intermediate value of the surface coverage of catalytic centers. The most significant featu...