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Updated: Aug 30, 2025

Characterization of Nanocrystal Size Distribution using Raman Spectroscopy with a Multi-particle Phonon Confinement Model
Published on: August 22, 2015
Electron-phonon coupling and vibrational properties of size-selected linear carbon chains by resonance Raman
P Marabotti1, M Tommasini2, C Castiglioni2
1Micro and Nanostructured Materials Laboratory-NanoLab, Department of Energy, Politecnico di Milano via Ponzio 34/3, I-20133, Milano, Italy.
Abstract:
UV resonance Raman spectroscopy of size-selected linear sp-carbon chains unveils vibrational overtones and combinations up to the fifth order. Thanks to the tunability of the synchrotron source, we excited each H-terminated polyyne (HCnH with n = 8,10,12) to the maxima of its vibronic absorption spectrum allowing us to precisely determine the electronic and vibrational structure of the ground and excited states for the main observed vibrational mode. Selected transitions are shown to enhance specific overtone orders in the Raman spectrum in a specific way that can be explained by a simple analytical model based on Albrecht's theory of resonance Raman scattering. The determined Huang-Rhys factors indicate a strong and size-dependent electron-phonon coupling increasing with the sp-carbon chain length.
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