Clusters diameter

FIGURE 36.5 Model calculation employed to study the dependence of the cluster diameter on the distance between the STM and the substrate surface for localized electrochemical nucle-ation and growth. The lower part of the figure shows the profile of the Nemst potential for the Co /Co potential as a function of the distance from the tip center. The fines indicate a constant Co concentration. (From Schindler et al., 2000, with permission from the American Institute of Physics.)... 

Figure 7. Optical absorption spectra of Au-implanted silica samples atmealed in air (a) or Ar (b) for 1 h at different temperatures, (c) Nonlinear fit (empty circles) to the optical absorption spectrum of the sample annealed at 900 °C in air, from which the average cluster diameter is obtained and compared to the TEM measured one, (d) Evolution of the optical spectra of Au-...

Based on this new model for the morphology of Nafion, the dimensional variations of the scattering entities with water content were used in simple space filling calculations to estimate the cluster diameter, the number of sulfonate sites per cluster, and the number of water molecules per cluster. The results of these model calculations showed that, for a given equivalent weight, the cluster diameter. 

Figure 13. Dependence of cluster diameter and number of SOs groups per cluster on water content in 1200 EW Nafion according to Gierke, Munn, and Wilson. (Reprinted with permission from ref 17. Copyright 1981 Wiley.)...

The final silver cluster diameter increases, at given initial Ag and PVA concentrations, for example from 15 to 50 nm (n 50 times larger), when the part of reduction is increasingly achieved by the donor SPV, rather than by radiolytic radicals [31]. A red shift correlates with the growth in size in the final optical surface plasmon band. Nonirradiated solutions of EDTA silver complex are stable because EDTA does not reduce the ions directly. However, after the appearance of the 400-nm spectrum of silver... 

Here we will present, as an example, all the results relative to the Si33BPH36 nanocrystal, whose relaxed structure is presented in Figure 15. The choice of the small Si33BPH36 cluster (diameter around 1 nm) is due to the fact that the GW-BSE calculation [116], necessary to obtain the many-body optical spectra, is very computationally demanding. 

The definition of cluster diameter dc remains the same with the original (Equation (6)), which read... 

Figure 3 Plot of AU and the area ratio R = AVBc/AVBb as a function of the Pt-Pt coordination number N, as obtained from the EXAFS analysis. Also shown is the estimated dispersion, cluster diameter and number of atoms/particle as estimated assuming spherical clusters and FCC packing. Data are shown for the acidic supports (LTL[K/A1=0.63] zeolite and CI-AI2O3, SiOi) and for the basic supports (LTL [K/A1=1.25] zeolite and K-AI2O3, K-Si02).

FIGURE 12 Average coordination number as a function of platinum cluster diameter for cuboctahedral clusters. 

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