Will Raman Shift depend on the molecule of the sample through which it travels or will it depend only on the excitation frequency
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I think you are a little confused about how raman scattering works- you have it the wrong way around! Raman scattering is a non-resonant process. A Raman shift is entirely dependent on the structure of the molecule, and independent of the excitation frequency. The observed Raman shift is a result of Raman scattering, a rare inelastic scattering event relative to typical elastic Rayleigh scattering.
raman scattering wikipedia page](https://i.sstatic.net/7nox9.png)
Raman scattering is when photons that are incident upon a molecule alter the its vibrational states. The photon will excite the molecule to a virtual state before the molecule relaxes to an altered vibrational state. The molecules state is changed after the interaction. As a result, the scattered photons energy is different to that of the incident photon, as it has exchanged some energy with the molecule. Typically the scattered photons are the result of energy lost to the molecule and are therefore red shifted (called a Stokes shift), but it can also gain energy and you can observe a blue shift (anti-Stokes).
If the scattered light is collected and sorted by frequency, you can see a raman spectra, which is a series of peaks that represent the various excited vibrational states that represent the bonds present in a molecule.
The wikipedia page for this process is very informative and I would highly recommend reading it if you are interested in Raman shifts.
