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arXiv · 0811.3285

Inelastic neutron scattering due to acoustic vibrations confined in nanoparticles: theory and experiment

Lucien Saviot·Caleb H. Netting·Daniel B. Murray·Stéphane Rols·Alain Mermet·Anne-Laure Papa·Catherine Pighini·Daniel Aymes·Nadine Millot
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Abstract

The inelastic scattering of neutrons by nanoparticles due to acoustic vibrational modes (energy below 10 meV) confined in nanoparticles is calculated using the Zemach-Glauber formalism. Such vibrational modes are commonly observed by light scattering techniques (Brillouin or low-frequency Raman scattering). We also report high resolution inelastic neutron scattering measurements for anatase TiO2 nanoparticles in a loose powder. Factors enabling the observation of such vibrations are discussed. These include a narrow nanoparticle size distribution which minimizes inhomogeneous broadening of the spectrum and the presence of hydrogen atoms oscillating with the nanoparticle surfaces which enhances the number of scattered neutrons.

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Lucien Saviot, Caleb H. Netting, Daniel B. Murray, Stéphane Rols, Alain Mermet, Anne-Laure Papa, Catherine Pighini, Daniel Aymes, Nadine Millot. 2008-11-20. Inelastic neutron scattering due to acoustic vibrations confined in nanoparticles: theory and experiment. https://doi.org/10.1103/physrevb.78.245426

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