Raman spectroscopy pdf

Raman spectroscopy :-
                                        1. Transmission :-
It is the passes of the electromagnetic radiation trough the medium (solid, liquid and gass)
2. Absorption
                            It is the absorption of radiation in the medium
3. Scattering :-
                           It phenomenon by which a beam of light is forced to deviate from its path in many different directions.

Rayleigh scattering:-
                                        Rayleigh observed that the frequency of scattered light (Vs) was equal to the frequency of incidents light ( Vi)
This type of scattering light in a transfer medium without any changes of incidents light is called Rayleigh scattering.
When the beam of light on the beam of light on scattered on a transfer medium then a small amount of radiation is scattered.

👉Raman scattering  (raman effect ):-
                            In 1928 Raman found that when a monochromatic radiation  was passed through a transferred medium then the scattered radiation was absorption some line of lower frequency and some lines of higher frequency in addition to the line corresponding to the incident radiation.
This type of scattering of light in transferred in which change in the frequency incidents light is called raman scattering.

👉Quantum theory of electromagnetic radiation  (EMR):-
                               According to quantum mechanics the strim flow of light which  heaving the energy are known as photon.
If the light or photon are allowed to incidents on the sample then the collision between sample molecule and photons are take place
There are two type of collision between molecule and photon
1.elastic collision
2. Non elastic collision
If the elastic collision are take place between molecule and photons then the scattering radiation having the some frequency and incidents radiation.
If the collision are inelastic then the energy transfer between photon molecule take place, in non elastic collision there are two types of collision transfer observed.
1. Photons to molecule energy transfer :-
                                                                        When during the rotation of electron of the energy transfer are take place photon toplexuses then the scattering radiation will have the lower frequency as campare to incidents radiation the corresponding spectral line in raman spectrum is called stock line.
2. Molecule to photon energy transfer:-
                                                                    In these conditions the scattering radiation with have the higher frequency as campare to incidents radiation the spectral line corresponding this type of scattering are known as anti stock line.
The energy change  is must be the energy difference between two radiation or vibration energy state.
If the energy state involve the vibration energy state then the resulting spectrum known as vibrational raman spectra .
वे अणु जिनके लिए दिधुरव आघूरण का मान शून्य होता है।
वे अणु रमन एक्टिव होते है