Table of Contents
- 1 Why does Stokes lines are stronger than anti-Stokes lines?
- 2 Why are anti-Stokes lines less intense?
- 3 How are Stokes lines different from anti-Stokes lines?
- 4 What are Stokes and anti Stokes lines in Raman spectrum?
- 5 What are Stokes and anti-Stokes lines in Raman scattering?
- 6 What is Stoke and anti-Stokes lines?
Why does Stokes lines are stronger than anti-Stokes lines?
As the number of atoms in the ground state is more than the number of atoms in the excited states, the Stokes lines are more intense than the anti Stokes lines.
Why are anti-Stokes lines less intense than Stokes lines in Raman spectrum?
The anti-Stokes lines will be much weaker than the Stokes lines because there are many more molecules in the ground state than in excited vibrational states.
Why are anti-Stokes lines less intense?
This occurs because in either case one vibrational quantum of energy is gained or lost. Also, note that the anti-Stokes line is much less intense than the Stokes line. This occurs because only molecules that are vibrationally excited prior to irradiation can give rise to the anti-Stokes line.
Which lines are most intense in the Raman spectrum answer a Stokes lines B anti-Stokes lines C Rayleigh lines D None of the above?
Explanation: The Rayleigh-scattered radiations are considerably more intense than either of the other two types – Strokes lines and Anti-Strokes lines.
How are Stokes lines different from anti-Stokes lines?
Stokes lines are of longer wavelength than that of the exciting radiation responsible for the fluorescence or Raman effect. Thus, anti-Stokes lines are always of shorter wavelength than that of the light that produces them.
Why does the ratio of anti-Stokes to Stokes intensities increase with sample temperature?
Why does the ratio of anti-stokes to stokes intensities increase with sample temperature? The number of molecules in the first vibrational level of the ground state increases as temperature increases. Thus, the ratio of anti-stokes to stokes intensity increases with increasing temperature.
What are Stokes and anti Stokes lines in Raman spectrum?
Stokes lines are of longer wavelength than that of the exciting radiation responsible for the fluorescence or Raman effect. Anti-Stokes lines are found in fluorescence and in Raman spectra when the atoms or molecules of the material are already in an excited state (as when at high temperature).
What is intensity of Raman line?
The intensity of the Raman scattering is proportional to this polarizability change. Therefore, the Raman spectrum (scattering intensity as a function of the frequency shifts) depends on the rovibronic states of the molecule.
What are Stokes and anti-Stokes lines in Raman scattering?
When temperature increases the intensity of Raman anti-Stokes line?
It has been observed that while according to Placzek’s theory the intensities should increase with temperature both for the Stokes and the anti-Stokes lines, experimental resutts show that there is a marked decrease in intensity for the Stokes lines with increase of temperature.
What is Stoke and anti-Stokes lines?
Stokes lines, radiation of particular wavelengths present in the line spectra associated with fluorescence and the Raman effect (q.v.), named after Sir George Gabriel Stokes, a 19th-century British physicist. Thus, anti-Stokes lines are always of shorter wavelength than that of the light that produces them.
Which type of scattering is the strongest?
Another finding is that forward scattering is stronger than backward scattering, because the relative phase differences of contributions from different scattering locations on the particles become smaller.