Finite-Size Effects and Surface-Enhanced Raman Scattering from Molecules Adsorbed on Noble-Metal Nanoparticles
نویسندگان
چکیده
We study the role of a strong electron confinement on the surface-enhanced Raman scattering from molecules adsorbed on small noble-metal nanoparticles. We describe a novel enhancement mechanism which originates from the different effect that confining potential has on s-band and d-band electrons. We demonstrate that the interplay between finite-size and screening efects in the nanoparticle surface layer leads to an enhancement of the surface plasmon local field acting on a molecule located in a close proximity to the metal surface. Our calculations show that the additional enhancement of the Raman signal is especially strong for small nanometersized nanoparticles.
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