Journal ArticleDOI
Theory of the optical properties of ionic crystal cubes
TLDR
In this paper, a theory for optical properties of particles of arbitrary shape, composed of a homogeneous isotropic material with a dielectric constant, was developed for the optical properties.Abstract:
A theory is developed for the optical properties of particles of arbitrary shape, composed of a homogeneous isotropic material with a dielectric constant $\ensuremath{\epsilon}(\ensuremath{\omega})$. The particles are so small that retardation can be neglected. An expression is obtained for the average dielectric constant of a medium containing a small fractional volume of particles. Calculations for a cube show that six resonances contribute to the optical absorption. They span a frequency range such that ${\ensuremath{\epsilon}}^{\ensuremath{'}}(\ensuremath{\omega})$, the real part of the dielectric constant, lies between -3.68 and -0.42, as contrasted with the single resonance for a sphere at ${\ensuremath{\epsilon}}^{\ensuremath{'}}(\ensuremath{\omega})=\ensuremath{-}2$. A comparison of the theory with experiments on the optical absorption of NaCl and MgO cubes shows that the width of the absorption peak can be explained by the frequency range of the cube resonances. Previous theories which assumed spherical particles required an unphysically high damping in $\ensuremath{\epsilon}(\ensuremath{\omega})$ to account for the width.read more
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Journal ArticleDOI
Shape‐Controlled Synthesis of Metal Nanocrystals: Simple Chemistry Meets Complex Physics?
TL;DR: A comprehensive review of current research activities that center on the shape-controlled synthesis of metal nanocrystals, including a brief introduction to nucleation and growth within the context of metal Nanocrystal synthesis, followed by a discussion of the possible shapes that aMetal nanocrystal might take under different conditions.
Journal ArticleDOI
Controlling the synthesis and assembly of silver nanostructures for plasmonic applications
Matthew Rycenga,Claire M. Cobley,Jie Zeng,Weiyang Li,Christine H. Moran,Qiang Zhang,Dong Qin,Younan Xia +7 more
TL;DR: In plasmonics, the metal nanostructures can serve as antennas to convert light into localized electric fields (E-fields) or as waveguides to route light to desired locations with nanometer precision through a strong interaction between incident light and free electrons in the nanostructure.
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Shape Control of Colloidal Metal Nanocrystals
TL;DR: In this paper, an overall picture of shaped metal particles is presented, with a particular focus on solution-based syntheses for the noble metals, emphasizing key factors that result in anisotropic, nonspherical growth such as crystallographically selective adsorbates and seeding processes.
Journal ArticleDOI
Gold nanorods: Synthesis, characterization and applications
TL;DR: An overview of gold nanorod synthesis and properties can be found in this article, where the shape-dependent optical properties of rod-shaped nanoparticles are discussed and a theoretical analysis of the expected behavior is presented.
Journal ArticleDOI
Shape effects in plasmon resonance of individual colloidal silver nanoparticles
TL;DR: In this paper, the effect of size and shape on the spectral response of individual silver nanoparticles was studied and it was shown that specific geometrical shapes give distinct spectral responses.