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please help me i need to memorize exactly the below essay
In 1928, Sir C.V. Raman discovered experimentally, that the
monochromatic light is scattered when it is allowed to pass through a
substance. The scattered light contains some additional frequencies
other than that of incident frequency. This is known as Raman effect.
The lines whose frequencies have been modified in Raman effect
are called Raman lines. The lines having frequencies lower than the
incident frequency are called Stoke’s lines and the lines having
frequencies higher than the incident frequency are called Anti−stokes
lines. This series of lines in the scattering of light by the atoms and
molecules is known as Raman Spectrum.
The Raman effect can be easily understood, by considering the
scattering of photon of the incident light with the atoms or molecules.
Let the incident light consist of photons of energy hνo.
1. If a photon strikes an atom or a molecule in a liquid, part of
the energy of the incident photon may be used to excite the atom of the
liquid and the rest is scattered. The spectral line will have lower
frequency and it is called stokes line.
2. If a photon strikes an atom or a molecule in a liquid, which is in
an excited state, the scattered photon gains energy. The spectral line will
have higher frequency and it is called Anti−stoke’s line.
3. In some cases, when a light photon strikes atoms or molecules,
photons may be scattered elastically. Then the photons neither gain nor lose energy. The spectral line will have unmodified frequency.
If νo is the frequency of incident radiation and νs the frequency of
scattered radiation of a given molecular sample, then Raman Shift or
Raman frequency Δν is given by the relation Δν = νο − νs.
The Raman shift does not depend upon the frequency of the
incident light but it is the characteristic of the substance producing
Raman effect. For Stoke’s lines, Δν is positive and for Anti–stoke’s lines
Δν is negative.
The intensity of Stoke’s line is always greater than the
corresponding Anti−stoke’s Line. The different processes giving rise to
Rayleigh, Stoke’s and Anti-stokes lines are shown in
When a system interacts with a radiation of frequency νo, it may
make an upward transition to a virtual state. A virtual state is not one
of the stationary states of the molecule. Most of the molecules of the
system return back to the original state from the virtual state which
corresponds to Rayleigh scattering. A small fraction may return to
states of higher and lower energy giving rise to Stoke’s line and Antistoke’s
line respectively.
Applications of Raman Spectrum
(i) It is widely used in almost all branches of science.
(ii) Raman Spectra of different substances enable to classify them
according to their molecular structure.
(iii) In industry, Raman Spectroscopy is being applied to study the
properties of materials.
(iv) It is used to analyse the chemical constitution.
how do i use the following methods for memorizing this:
1.major mnemonic system
2.peg method
3.memory palace
4.roman room method
5.visualize
i understood everything and i tried recording the information and even flashcards but i can't recall the information
In 1928, Sir C.V. Raman discovered experimentally, that the
monochromatic light is scattered when it is allowed to pass through a
substance. The scattered light contains some additional frequencies
other than that of incident frequency. This is known as Raman effect.
The lines whose frequencies have been modified in Raman effect
are called Raman lines. The lines having frequencies lower than the
incident frequency are called Stoke’s lines and the lines having
frequencies higher than the incident frequency are called Anti−stokes
lines. This series of lines in the scattering of light by the atoms and
molecules is known as Raman Spectrum.
The Raman effect can be easily understood, by considering the
scattering of photon of the incident light with the atoms or molecules.
Let the incident light consist of photons of energy hνo.
1. If a photon strikes an atom or a molecule in a liquid, part of
the energy of the incident photon may be used to excite the atom of the
liquid and the rest is scattered. The spectral line will have lower
frequency and it is called stokes line.
2. If a photon strikes an atom or a molecule in a liquid, which is in
an excited state, the scattered photon gains energy. The spectral line will
have higher frequency and it is called Anti−stoke’s line.
3. In some cases, when a light photon strikes atoms or molecules,
photons may be scattered elastically. Then the photons neither gain nor lose energy. The spectral line will have unmodified frequency.
If νo is the frequency of incident radiation and νs the frequency of
scattered radiation of a given molecular sample, then Raman Shift or
Raman frequency Δν is given by the relation Δν = νο − νs.
The Raman shift does not depend upon the frequency of the
incident light but it is the characteristic of the substance producing
Raman effect. For Stoke’s lines, Δν is positive and for Anti–stoke’s lines
Δν is negative.
The intensity of Stoke’s line is always greater than the
corresponding Anti−stoke’s Line. The different processes giving rise to
Rayleigh, Stoke’s and Anti-stokes lines are shown in
When a system interacts with a radiation of frequency νo, it may
make an upward transition to a virtual state. A virtual state is not one
of the stationary states of the molecule. Most of the molecules of the
system return back to the original state from the virtual state which
corresponds to Rayleigh scattering. A small fraction may return to
states of higher and lower energy giving rise to Stoke’s line and Antistoke’s
line respectively.
Applications of Raman Spectrum
(i) It is widely used in almost all branches of science.
(ii) Raman Spectra of different substances enable to classify them
according to their molecular structure.
(iii) In industry, Raman Spectroscopy is being applied to study the
properties of materials.
(iv) It is used to analyse the chemical constitution.
how do i use the following methods for memorizing this:
1.major mnemonic system
2.peg method
3.memory palace
4.roman room method
5.visualize
i understood everything and i tried recording the information and even flashcards but i can't recall the information
