Phonon characterization of nano-crystals by Raman spectroscopy

Proposed herein is a method based on the Levenberg–Marquadt technique to retrieve an approximated average phonon dispersion curve from Raman spectra of nano-sized crystals. To this end we deal with a modified form of the well-known phonon confinement model in which the intrinsic linewidth Γ0 is replaced by an effective linewidth Γ. An application to experimental results obtained on TiO2 nano-crystals is presented as a test of the method.