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Updated: Jul 13, 2026

Characterization of Nanocrystal Size Distribution using Raman Spectroscopy with a Multi-particle Phonon Confinement Model
Published on: August 22, 2015
Low-frequency vibrational properties of nanocrystalline materials
P M Derlet1, R Meyer, L J Lewis
1Paul Scherrer Institute, 5232 Villigen, Switzerland.
Abstract:
The vibrational density of states (VDOS) of bulk nanocrystalline Ni and Cu (model) samples with grain diameters between 5 and 12 nm are derived from molecular-dynamics simulations. The results show an enhancement of the density of states at low and high energies. Because of large system sizes and a decomposition of the VDOS into grain and grain-boundary components, the low-frequency region can be investigated for the first time. It is found that the anomalous increase of the VDOS is mainly caused by the high number of grain-boundary atoms and that a power-law behavior of the low-frequency grain-boundary VDOS exists, which suggests a reduced dimensionality effect.
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