Silver clusters charge

B) Silver Atoms and Clusters in Faujasite Zeolites It has been shown recently by diifierent techniques that small, charged silver clusters can be formed and stabilized in the cavities of zeolites A, X and Y. Uytterhoeven et al (3b) have shown that... 

Zeolites are attractive host materials as they present regular channel systems, providing crystallographic defined locations for metal clusters. Hence, the size of the clusters inside the zeolites can be limited by the dimensions of their channels and cages. Zeolite-supported noble metal catalysts were extensively studied due to their wide application as catalysts in petroleum industry.Reduction of silver in zeolite hosts has been carried out by /-irradiation.The intermediate paramagnetic (charged) silver clusters formed in /-irradiated silver-exchanged zeolites have been studied by electron spin resonance (ESR)... 

Coadsorption phenomena in heterogeneous catalysis and surface chemistry quite commonly consider competitive effects between two reactants on a metal surface [240,344]. Also cooperative mutual interaction in the adsorption behavior of two molecules has been reported [240]. Recently, this latter phenomenon was found to be very pronounced on small gas-phase metal cluster ions too [351-354]. This is mainly due to the fact that the metal cluster reactivity is often strongly charge state dependent and that an adsorbed molecule can effectively influence the metal cluster electronic structure by, e.g., charge transfer effects. This changed electronic complex structure in turn might foster (or also inhibit) adsorption and reaction of further reactant molecules that would otherwise not be possible. An example of cooperative adsorption effects on small free silver cluster ions identified in an ion trap experiment will be presented in the following. 

This work shows that a positively charged site provides an energetically favorable site for silver cluster growth on AgBr. Certainly the site need not be restricted to the positive kink site as we considered in this work. Any site with partial positive charge will suffice. The important point is that the site determines the path of growth and in particular its charge plays a dominant role. 

Figure 8 (a) Charging of bare metal clusters (Equation (28)) in water, dichloromethane, and alkane solvents, (b) Experimental data for copper clusters in the gas phase and silver clusters in water. ... 

A conformational effect of the silver cluster is a fixing of those parts of the dipeptide that are directly attached to it. Molecular parts further away are still loose [Fig. 10(b)] and moving. A density difference of the excited state and the ground state [Fig. 10(d)] shows that the major charge redistribution takes place at the cluster site. 

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