Silver optical spectra

Experimental samples were fabricated using the vacuum device VU-IA by means of successive thermal evaporation of copper and silver. Optical spectra were recorded with the Cary 500 spectrophotometer. The film structure was studied with the use of the atomic force microscope "Solver P47 - PRO" in a contact regime. 

Optical Spectrum and Airshock from a 500-Ton TNT Explosion , NOLTR-67-94, Naval Ordn Lab, Silver Spring (1967) 51) T.C. Chamness... 

Sampling in surface-enhanced Raman and infrared spectroscopy is intimately linked to the optical enhancement induced by arrays and fractals of hot metal particles, primarily of silver and gold. The key to both techniques is preparation of the metal particles either in a suspension or as architectures on the surface of substrates. We will therefore detail the preparation and self-assembly methods used to obtain films, sols, and arrayed architectures coupled with the methods of adsorbing the species of interest on them to obtain optimal enhancement of the Raman and infrared signatures. Surface-enhanced Raman spectroscopy (SERS) has been more widely used and studied because of the relative ease of the sampling process and the ready availability of lasers in the visible range of the optical spectrum. Surface-enhanced infrared spectroscopy (SEIRA) using attenuated total reflection coupled to Fourier transform infrared spectroscopy, on the other hand, is an attractive alternative to SERS but has yet to be widely applied in analytical chemistry. 

However, in an attempt to integrate the SFA and spectroscopic techniques, the use of silver for optical interferometry has been seen as a drawback due to the fact that it precluded sufficient excitation source intensity to illuminate the buried interface. In order to circumvent this problem Mukhopadhyay and co-workers in an experimental set-up where the SFA was combined with fluorescence correlation spectroscopy (FCS) used, instead of silver, multilayer dielectric coatings that allowed simultaneous interferometry and fluorescence measurements in different regions of the optical spectrum [75]. Using this set-up they succeeded in measuring diffusion in molecularly thin films with singlemolecule sensitivity. 

Figure 2. Optical spectrum of silver nano

Figure 3 Left Optical absorption spectrum and STM image of radiation-induced oligomers Agv at partial reduction and stabilized by PA [85,86]. Right Absorption spectrum of radiation-induced silver clusters Ag in the presence of EDTA. (a) After partial reduction (10 krad), (b) after 4 days, (c) after 8 days. Inset TEM micrographs of (a), (b), (c), and electron diffraction pattern of sample c. (From Ref 145.)...

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... 

---