Silver frequency factor

The following values of the specific edge energy and the frequency factor fci are considered as most probable at the time being for the cubic and octahedral faces of silver in 6M AgNOa at 318 K ... 

Another important factor in the selection of a lead alloy is fatigue strength, which may arise from high-frequency vibration from pumps and stirrers or from differential expansion from heat and cooling cycles. The marked increase of fatigue strength obtained by alloying with copper, silver and tellurium can be seen from Table 3.25. 

The first NeNePo experiments dealt with silver clusters, Ag3, Ags, Ag7, and Ag9, particularly with the first of these. The photodetachment and photoionization were done with a single titanium-sapphire laser producing pulses of approximately 60 fs duration. Doubled in frequency, these could be tuned over a wavelength span from above 420 to below 390 nm. As with the dimer, photodetachment was a one-photon process and photoionization a two-pho-ton process. (The clusters of odd numbers of atoms could be studied this way the even-numbered clusters require at least three photons in the available energy range for photoionization). The interval between pulses could be varied from zero (simultaneous pulses) to 100 ps the two pulses were made to differ in intensity by about a factor of 2, and either could be the leading pulse. 

Simultaneous account for local field and local density of photon states enhancements in close proximity to a silver ellipsoidal nanopaiticle is found to provide up to 10 -fold Raman scattering cross-section rise up. A model of the so-called hot points in surface enhanced spectroscopy has been elaborated as local areas with high Q-factor at incident and scattered (emitted) light frequencies. Further experiments are proposed towards verification of the model in terms of transient Raman experiments to clarify incident field enhancement and scanning near-field optical mapping of local density of photon states. 

Arya and Zeyher " develop a general many-body theory for SERS. In the limit of a planar surface and only plasmon contributions to the interactions, they find an enhancement of a factor of 100 for the renormalization model and it is relatively weakly dependent on the excitation frequency. This is for silver of course. For Cu or Au, they predict even smaller image effects, <10. 

The spectra of aromatic amino acids and histidine were first reported by Nabiev et al. [85]. The spectra of other amino acids and short peptides adsorbed on silver electrode or silver vere also later published (see Table 5). However, the spectra of the same amino acids published by various authors showed fairly large variations in relative band intensities and frequencies. The quality of SERS spectra depends on many factors, such as the method of preparation and degree of aggregation of the colloids, pH of medium, concentration of adsorbate, etc. [83]. In view of the facts mentioned above, conditions need to be carefully controlled in order to obtain reproducible results. As the description of experimental conditions published to date is rather poor, it is difficult to explain the observed difference. The common features deduced from the SERS spectroscopic studies of amino acids are as follows ... 

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