Raman
Hermes / Raman
Raman Spectroscopy
Raman spectroscopy is a form of vibrational spectroscopy. Raman spectroscopy provides information about molecular vibration can be used for sample identification and quantitative analysis. Method a sample of a monochromatic light source (i.e. laser) includes sending the sample surface and analyzing the scattered light. When the light scattered by the substance, scattering occurs in almost all my elastic (Rayleigh scattering) and not a change in energy. However, a very small percentage of the inelastic scattering takes place. In this case, the scattered light, will have a different energy from incoming light. This inelastic scattering of light, are provided in 1923 by Adolf Smekal theoretically and experimentally was observed first in 1928 by Chandrasekharan to C. V. Raman.
Raman scattering, infrared absorption spectroscopy is a spectroscopic technique completed.Raman, by mid IR and near IR spectroscopy offers several advantages:
• Sample preparation is minimal or no required
• Water is a poor dispersant – no special accessories for the measurement of aqueous solutions
• Water and CO2 vapor is very weak dispenser – sample without removal is unnecessary
• most cases the idela cheap glass sample containers
• optical fiber for remote analysis (up to 100 m long) can be used
: • the basic mode measured Raman band can be easily associated with the chemical structure
• Raman spectra in the mid-IR spectrum “cleaner” – RAMAN bands are narrower and overtone / tape combination is usually poor.
• Standard spectral range from 400 cm-1 reaches to the very bottom, and these techniques is ideal both organic to inorganic species
• Raman spectroscopy, weak symmetric bonds bands in an infrared spectrum (e.g., -SS-, -C-S-, -C≡C-) it used to measure.
Samples were Raman spectroscopy can be found in the following form,
• solid (particle, pellet, powder, film, fiber)
• Liquid (gel, paste)
• Gas