Electron transfer efficiency

Cai Z, Sevilla MD (2003) In G. Schuster (ed) Long-range electron transfer efficiency within DNA, Topics in Current Chemistry. Springer, Berlin Heidelberg New York (this volume)... 

Intermolecular light-induced electron transfer to acceptors (quinones and nitro-benzenes) complexes in a /(-cyclodextrin linked to a porphyrin has been studied and the dependence of electron transfer efficiency upon the reduction potential of the acceptor was examined 72). 

Reactions 2 and 3 have been proposed as the primary mode of catalysis for Co (30), Mn (31), and Cr (32). However, it must be pointed out that metal reactivity can change tremendously with complexing agent, which shifts redox potentials, and with solvent, which alters acid/base properties and electron transfer efficiency. Electron transfer oxidations to generate L are extremely rapid in nonpolar media (33, 34), including neat oils, and are less efficient in aqueous or polar protic solvents. 

The ratio of ferrocene-modified siloxane subunits to unsubstituted siloxane subunits rrv.n ratio) was varied as was the length (a ) of the alkyl side chain onto which the ferrocene moiety was attached as shown in Fig. 3.3. The electrode containing co-polymer with m n ratio of 1 1 or 1 2 was the more efficient electron relay systems. The ferrocene-modified homopolymer on the other hand loses flexibility due to steric hindrance caused by the side chain substitution by ferrocene, preventing efficient electron transfer from the enzyme to the electrode. The length of the alkyl side chain onto which the ferrocene moiety is attached was also found to influence the electron transfer efficiency of the electron relay system. Maximal current density was measured... 

The mechanism of the change of fluorescence intensity of xanthene-based fluorescent sensors was also studied, and it was hypothesized that photo-induced electron transfer between the xanthene and 9-aromatic moiety might be important. Nagano and Urano et al. systematically synthesized xanthene derivatives bearing various substituted phenyl groups at the 9-position, and confirmed that electron transfer has a significant role in their fluorescence properties they also showed that the determinants of electron transfer efficiency are physical parameters of the xanthene or... 

Apart from their light-absorption characteristics, the polypyridine complexes are attractive photochemical substrates because, with the possible exception of [Ir(bipy)j] for which no data are available, the quantum yields for formation of the ESs are near unity. Furthermore, the ESs are long lived and undergo only slow reaction with solvent. As a consequence, the ESs are formed in high yields and undergo bimolecular electron transfer efficiently. 

On the other hand, the 2 infinite value increases with the film thickness, which reflects an expansion of the macromolecular domain, i.e. increase of the redox sites. At intermediate thickness of the polymer layer, the electron-transfer reaction proceeds most rapidly. Further increase of the thickness brings about the steep decrease in the reaction rate via the electron-transfer process, probably caused by the decrease in the electron-transfer efficiency. 

Gou, P, Hanke, G.T., Kimata-Ariga, Y., Standley, D.M., Kubo, A., Taniguchi, I., Nakamura, H., and Hase, T. (2006). Higher order structure contributes to specific differences in redox potential and electron transfer efficiency of root and leaf ferredoxins. Biochemistry 45, 14389-14396. 

Electron will be transferred via the protein matrix and the protein-protein interface. Therefore, one should ask whether the structure and the dynamics of the proteins play an important role in the determination of the rate of this electron transfer or not Also, the relative orientation and distance of the two redox potential centers will have another detemiinant role in the electron transfer efficiency. 

Ncultalizafrcm of heme propionates inilu a more productive protein doddng increasing tty that electron transfer efficiency. Therefore, although the affinity of the complex is the same because the area of the two proteins interaction did not change, the orientation of the two proteins within the complex is more favorable to dectron transfer. 

In the test sheets of PMTs, the manufacturers occasionally specify the measured anode luminous sensitivity" instead of the cathode sensitivity. The anode sensitivity is the cathode sensitivity (including the electron transfer efficiency) multiplied by the gain of the tube. Because almost any gain can be obtained by increasing the supply voltage, the anode luminous sensitivity cannot be used to compare the photon counting performance of PMTs. 

This methodology was extended to other energy-transfer systems giving results pointing out the importance of the sugar unit connected to the electron-donor and electron-acceptor to control the electron-transfer efficiency [76]. 

The efficiency of photovoltaic devices depends on both the photoin-duced charge generation, which is based on the electron transfer efficiency and the transport of charges created to the electrodes, i.e., the charge carrier mobility. These two issues must be fulfilled simultaneously. It is possible to construct a structural arrangement of the device materials in order to enhance both demands in a microscopic region separately. 

---