Can Raman be used to distinguish different phases and polymorphs of a material?

Yes.  In most cases Raman scattering is sensitive to material phase, polymorphism and solid form.  Thus, even though two materials may have identical chemical formulae their different crystal structure or phase will often result in distinct spectra.  Phase changes are often clearly distinguished within the spectrum, but other structural differences such as polymorphism can reveal themselves only through very subtle spectral changes.  In this case, it is often necessary to work with high spectral resolution to allow the minor changes to be confidently characterised.

Raman spectra of rutile (red) and anatase (blue) phases of titanium dioxide, showing significant spectral differences for fast identification
Raman spectra of rutile (red) and anatase (blue) phases of titanium dioxide, showing significant spectral differences for fast identification
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