Near-neighbor shell

Natural iteration method Nearest-neighbor approxmiation Near-neighbor shell Ni-Al... 

For a near-neighbor shell of atoms (Nt) whose interatomic vector with the absorber makes some angle 0, relative to the plane of polarization, one can relate the effective coordination number (Nf) and the true coordination number through57... 

In wave-vector form, the EXAFS can be expressed as a summation over the various coordination (near neighbor) shells and is given by... 

Figure 19. Fourier transform of the Pt L3 EXAFS acquired during (A) the oxidation and (B) the reduction of a carbon supported Pt catalyst electrode as a function of time. Note that the Fourier transforms have not been phase corrected. The peak at 2.24 A corresponds to the first shell of Pt near neighbors at 2.76 A. The peak at 1.50 A is a combination of the side-lobe from the Pt shell and a shell of O near neighbors at 2.01 A. (Reproduced with permission from ref 43. Copyright 1995 ElsevierSequoia S.A., Lausanne.)...

High resolution SI NMR spectra of galloslllcates with the faujaslte structure exhibit relative peak Intensities similar to faujaslte Indicating similar distributions of T atoms. However, the peaks In the gallium containing zeolites are deshielded by an amount nearly proportional to the number of gallium atoms In the first neighbor shell. 

The various absorption lines have been assigned with the help of MS-Xa calculations. Because the main influence on the shape of the XANES spectra is from the atoms in the first neighbor shell, only constituent clusters have been treated in the simulations, e.g., P033 for P406 and P043- for P4O10. In terms of this approximation, some details of the spectra (e.g., intensity and line widths of the absorptions) could be simulated sufficiently, whereas the predicted term values calculated for transitions near the absorption edge lie too close to each... 

The metals Eu and Yb have very different electronic structures from their near neighbors. They are both divalent, and their 4f occupancy, 4f and 4f, is one more than what one would expect from interpolating between their nearest neighbors. The 4f shell appears to be highly stable when it is half-filled or completely filled, to the extent that in these metals one valence electron goes... 

Fig. 5. The one that has non-zero values only near q=0.0 corresponds to twelve Cu atoms on the nn-shell, ci=100%. It is known that an atom on a site surrounded by like atoms behaves somewhat like an atom in a pure crystal, and would have little net charge. The conditional probability centered near q=0.2 corresponds to ci=0%, with all the neighboring atoms Zn. Such an atom behaves like a Cu impurity in a Zn crystal. The probabilities Pcu(ci,q) for ci=25%, 50%, and 75% have their centers between these limits, llte conditional probabilities have a structure themselves. Extrapolating, it should be possible to write Pcu(ci>q) a sum of the conditional probabilities Pcu(ci,C2,q) where C2 is the concentration of Cu atoms on the second nn-shell. That probability could, in turn, be written as the sum of probabilities PCu(ci,C2,C3,q), where eg is the concentration of Cu atoms on the third nn-shell.

Supporting evidence was given (7,17) for restricting the count to scales sufficiently separated from neighboring scales to respond as independent individuals to the applied oil film. However, oil entered and was retained by scales too near each other for them to be used for mortality counts. If the number and density of these scales were variable, some influence may have been exerted on the relation of the oil film to the individuals coimted. To enhance e independence of each scale coimted, fertile female scales were hand-thinned to approximately 0.5 cm. apart. The adult male insect emerges from the shell covering at an age of about 21 days only the cast shells of the males remain on the fruit at 36 days. These are loose and may be removed easily with an air stream. Any unfertile females are removed at the same time. 

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