Glasses Raman scattering

Sample preparation is straightforward for a scattering process such as Raman spectroscopy. Sample containers can be of glass or quartz, which are weak Raman scatterers, and aqueous solutions pose no problems. Raman microprobes have a spatial resolution of - 1 //m, much better than the diffraction limit imposed on ir microscopes (213). Eiber-optic probes can be used in process monitoring (214). 

A number of reviews have appeared covering the various aspects of borate glasses. The stmcture, physical properties, thermochemistry, reactions, phase equihbria, and electrical properties of alkah borate melts and glasses have been presented (73). The apphcation of x-ray diffraction, nmr, Raman scattering, in spectroscopy, and esr to stmctural analysis is available (26). Phase-equihbrium diagrams for a large number of anhydrous borate systems are included in a compilation (145), and thermochemical data on the anhydrous alkah metal borates have been compiled (17). 

Fig. 4.56. Schematic diagram of a SERS-active substrate and the measurement arrangement. Alumina nanoparticles are deposited on a glass surface and produce the required roughness. A thin silver layer is evaporated on to the nanoparticles and serves for the enhancement. Organic molecules adsorbed on the silver surface can be detected by irradiation with a laser and collecting the Raman scattered light.

Denisov, V. N., Mavrin, B. N. and Podobedov, V. B. (1987) Hyper-Raman scattering by vibrational excitations in crystals, glasses and liquids. Phys. Rep., 151, 1-92. 

Kirillov, S. A., Yarniopoulos, S. N., Charge-current contribution to low-frequency Raman scattering from glass-forming ionic liquids, Phys. Rev. B, 61, 11391-11399 (2000). 

Mulvaney S.P., Musick M.D., Keating C.D., Natan M.J., Glass-coated, analyte-tagged nanoparticles A new tagging system based on detection with surface-enhanced Raman scattering, Langmuir 2003 19 4784-4790. 

Figure 4. The sample cell arrangement in the DCSHG experiment, where the sample solution was inserted between two glass slips (lop), and the optical design for the DCSHG dispersion experiment, where the compressed H gas medium was pumped by a tunable pulsed dye laser source for Stokes generation by stimulated Raman scattering (bottom). (E° is the static electric field.) Key beam guiding prisms P, Stokes...

Figure 3. Resonance Raman spectrum of purple acid phosphatase. Protein (5 mM) maintained at 5 C In a glass Dewar and probed with 514.5 nm excitation (within the 560 nm phenolate + Fe(III) CT band, e = 4,000 cm" M The broad, underlying feature from 400-550 cm"1 Is due to Raman scattering from glass. (Reproduced from Ref. 14. Copyright 1987 American Chemical Society.)...

Konijnendijk, W. H. Stevels, J. M. 1975. The structure of borate glasses studied by Raman scattering. Journal of Non-Crystalline Solids, 18, 307-331. 

The sample gas normally is contained in glass tubing of diameter 1-2 cm and thickness 1 mm. The gas can be sealed in a small capillary tube whose diameter is slightly larger than that of the laser beam ( 1 mm). For weak Raman scatterers, an external resonating setup is used to increase their Raman intensity by multiple passing of the laser beam through the sample (Fig. 2-20A). 

Konijnendijk, W. L., and J. M. Stevels (1976). The structure of borosilicate glasses studied by Raman scattering. J. Noncryst. Solids 20, 193-224. 

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