13-05-2013, 04:54 PM
Introduction to Raman Spectroscopy
Raman.ppt (Size: 2.96 MB / Downloads: 82)
Chandrasekhara Venkata Raman
1888-1970
Discovered the inelastic scattering phenomenon in 1928
Was awarded the Nobel Prize for Physics in 1930
Raman spectroscopy probes the vibration modes of materials, much like infrared (IR) spectroscopy.
However, whereas IR bands arise from a change in the dipole moment, Raman bands arise from a change in the polarizability.
In many cases, transitions that are allowed in Raman are forbidden in IR, so these techniques are often complementary.
Applications of Raman Spectroscopy
Raman Spectroscopy is a method of determining modes of molecular motions, especially
vibrations. It is predominantly applicable to the qualitative and quantitative analyses of
covalently bonded molecules.
Extra:
-Identification of phases (mineral inclusions, composition of the gas phase inclusions)
-Anions in the fluid phase (OH-, HS-, etc.)
-Identification of crystalline polymorphs (Sillimanite, Kyanite, andalusite, etc.)
-Measurement of mid-range order of solids
-Measurement of stress
-High-pressure and High-temperature in situ studies
-Phase transition and order-disorder transitions in minerals (quartz, graphite)
-Water content of silicate glasses and minerals
-Speciation of water in glasses