Question

Question 5 : Raman lines on the low
frequency side of the excitation frequency
are called
Stokes lines
anti-Stokes lines
Rayleigh line
overtones​

Answer 1

Answer:

Raman scattering or the Raman effect /ˈrɑːmən/ is the inelastic scattering of photons by matter, meaning that there is an exchange of energy and a change in the light's direction. Typically this involves vibrational energy being gained by a molecule as incident photons from a visible laser are shifted to lower energy. This is called normal Stokes Raman scattering. The effect is exploited by chemists and physicists to gain information about materials for a variety of purposes by performing various forms of Raman spectroscopy. Many other variants of Raman spectroscopy allow rotational energy to be examined (if gas samples are used) and electronic energy levels may be examined if an X-ray source is used in addition to other possibilities. More complex techniques involving pulsed lasers, multiple laser beams and so on are known.

Light has a certain probability of being scattered by a material. When photons are scattered, most of them are elastically scattered (Rayleigh scattering), such that the scattered photons have the same energy (frequency, wavelength and color) as the incident photons but different direction. Rayleigh scattering usually has an intensity in the range 0.1% to 0.01% relative to that of a radiation source. An even smaller fraction of the scattered photons (approximately 1 in 10 million) can be scattered inelastically, with the scattered photons having an energy different (usually lower) from those of the incident photons—these are Raman scattered photons.[1] Because of conservation of energy, the material either gains or loses energy in the process.

Rayleigh scattering was discovered and explained in the 19th century. The Raman effect is named after Indian scientist C. V. Raman, who discovered it in 1928 with assistance from his student K. S. Krishnan. Raman was awarded the Nobel prize in Physics in 1930 for his discovery. The effect had been predicted theoretically by Adolf Smekal in 1923

Answer 2

Answer:

The line which appears on the low-frequency side of the exciting frequency i.e. known as the Stokes line.

Explanation:

STROKES LINES:

• A standard Raman spectrum is targeted on the frequency of incident light (typically a laser mild withinside the seen a part of the electromagnetic spectrum), with very excessive depth owing to Rayleigh scattering.
• Stokes lines may be located closer to the decreased frequencies and anti-Stokes may be visible closer to the better frequencies, later they're reflected in the middle of the Raman spectrum.
• Nevertheless, Stokes lines are extra extreme in contrast with the anti-Stokes counterparts, due to the fact the vibrational ground state is extra populated than excited states.
• Stokes lines are shaped of longer wavelength than that of the thrilling radiation liable for the fluorescence or Raman effect

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