NiFe complex

In multiple-layer thin films, it is possible that some of the elements may be present simultaneously in two or more layers. XRF analysis of this type of film can be complicated and cannot be made solely from their observed intensities. Additional information, such as the compositions or thickness of some of the layers is needed. The amount of addidonal non-XRF information required depends on the complexity of the film. For example, in the analysis of a FeMn/NiFe double-layer film, the additional information needed can be the composition or thickness of either the FeMn or NiFe layer. Using the composition or thickness of one of the film predetermined from a single-layer film deposited under identical condidons, XRF analysis of the FeMn/NiFe film was successfiil. ... 

We will use here the main results obtained for two complex and distinct situations the structural and spectroscopic information gathered for D. gigas [NiFe] hydrogenase and AOR, in order to discuss relevant aspects related to magnetic interaction between the redox centers, intramolecular electron transfer, and, finally, interaction with other redox partners in direct relation with intermolecular electron transfer and processing of substrates to products. 

Although the mechanistic insights for the model complex of [FeFe] hydrogenase became clearer little by little, those for the [NiFe] hydrogenase are still challenging topics. 

Heterodinuclear Ni-Fe complexes, which are not stabilized by the phosphine and NO ligands, were synthesized by Tatsumi and coworkers as [NiFe] hydrogenase mimics [208-210]. Several examples are shown in Fig. 8. However, the catalytic activities of these complexes are not ascertained. 

Fig. 9 Electrochemical H2 generation catalyzed by complex 27 as a model for the [NiFe] hydrogenase...

In view of the low Nin/Niin redox potential of [NiFe] hydrogenase, the search for low-potential Nin/Niin complexes not only with pure S-donor but also with mixed N/S environment has been of major interest, and significant advances in this field have been reported.298,299 Various mononuclear systems are listed in Figure 1 according to their redox potentials (usually in DMF). Homodinuclear Ni2 and heterodinuclear NiM complexes with N/S donor ligands, in particular... 

The design of complex NiFe compounds which mimic active site of hydrogenase and have the catalytic activity comparable with pure enzyme. 

Group 10. NiFe hydrogenase in the formate hydrogen lyase complex... 

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