Electron Transfer in the System, Tris-(1,10-phenanthroline)-cobalt(II)−Tris-(1,10-phenanthroline)-cobalt(III)

Abstract

The rates of electron transfer in the system tris-(l,10-phenanthroline)-cobalt(II)-tris-(l,10-phenanthroline)-cobalt(III) and analogous 2,2'-bipyridine and 2,2 ',2 "-tripyridine systems have been studied by a tracer technique. The rate laws as well as rate constants depend upon the anion present and the results are discussed in terms of ion-association. The rate is the same in D20 as in water but decreases in acetone-water solutions with increasing acetone concentration. The latter effect is discussed in terms of the barrier tunneling model for electron transfer. The rates and energy of activation are compared to those of other cobalt systems and the results are discussed in terms of the field strength of the ligand, metal ion electron configuration and shielding or conducting nature of the ligand.

Electron Transfer and Spectral α‐Band Properties of the Di‐Heme Protein Cytochrome c4 from Pseudomonas Stutzeri

“…Millipore water (Milli-Q Housing) was used throughout. The perchlorate salts of the cobalt(II1) complexes were prepared and characterized by reported procedures [46,47]. Co(I1) complexes were prepared in situ by mixing CoC1, with slightly more than the equivalent amount of ligand.…”

Electron transfer patterns of the di-heme protein cytochrome c4 from Pseudomonas stutzeri

“…½CoðbipyÞ 3 2þ was prepared as a 6 mM stock solution from CoCl 2 , 6H 2 O and a slight excess of bipy. [Co(bipy) 3 ]Cl 3 , Â H 2 O was prepared by published procedures [29] and stored as a 4 mM stock solution. All solutions contained 20 mM Tris/HCl buffer, pH 7.5.…”

Electrochemical detection of lateral charge transport in metal complex-DNA monolayers synthesized on Si(111) electrodes

“…4b) for another octahedral trication, CoðbipyÞ 3þ 3 , shows pure negative feedback (insulating behaviour). We attribute this behaviour to the much lower self-exchange rate for this complex (2 M À1 s À1 [105]) compared to RuðNH 3 Þ 3þ=2þ 6 (800-4300 M À1 s À1 [106][107][108]) which results in negative feedback due to low values of k O and k eff in the regime described by Eq. (10).…”