Raman spectroscopy was invented by scientist C.V Raman and involves scattering of electromagnetic radiation when it interacts with a substance. There are three types of scattering - Rayleigh scattering which involves no energy exchange, Stokes scattering where scattered radiation intensity is less than incident, and anti-Stokes scattering where intensity is more. A Raman spectrum shows Raman shifts which can be explained by quantum theory. A comparative study of IR and Raman spectra shows the rule of mutual exclusion, where in molecules like CO2, vibrations active in IR are inactive in Raman and vice versa.
1. Raman Spectroscopy
Invented by Scientist C.V Raman
Scattering of electromagnetic
radiation, Rayleigh scattering, Raman
scattering, nature of Raman
spectrum, Stoke’s lines, anti-Stoke’s
lines, Raman shift, quantum theory
of Raman spectrum, comparative
study of IR and Raman spectra, rule
of mutual exclusion- CO2 molecule.
2. UV electromagnetic radiation strike
on the substance some amount is
absorbed,some is scattered and
some radiation is transmitted
If the intensity of scattered radiation
is less than the incident-stoke
scattering
3. If the intensity of scattered radiation is
more than the incident- anti stoke
scattering
If there is no exchange of energy
between light photon and the matter-
rayleigh scattering
4. In carbon dioxide molecule those
vibration are IR active, they are
Raman inactive and vice versa.
