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Research concerning the production of trimetallic particles of silver-gold-platinum is presented. The process involves the catalytic use of gold-platinum core-shell particles in an aqueous solution of silver ions.

The function of the film elongation was studied through the analysis of the polarization spectra of template-synthesized colloidal gold rods with aspect ratios ranging from L/d=1.8 to 49 embedded in poly(vinyl alcohol) films. Only one resonance band instead of two absorbance bands as found for randomly distributed gold rods were shown by the polarization absorbance spectra of aligned systems. The rods were completely oriented when the film was stretched 4-6 times its original length as revealed by the visible and near-infrared spectra.

The potential application of nanometer-scale colloidal particles in optoelectronic devices and single-molecule detection initiated scientific interest on their size and shapes. A study was conducted on a population of novel nanoparticles in heterogeneous silver colloids. Surface-enhanced Raman scattering (SERS) analysis was performed. The findings illustrate that nanoparticle enhancement in the colloidal samples was correlated with particle size. Moreover, the optical enhancement can achieve a maximum of 10%-15% using size-selective fractionation techniques.

The method of Cumberland that can be adapted to prepare Mn(super 2+)- doped ZnSe nanoparticles is demonstrated. The results stated that a uniform and homogenous distribution of Mn(super 2+) in the nanoparticle was not achieved; consequently, the Mn(super 2+) ions lie toward the surface of the nanoparticles and possibly occupy two different sites in the nanoparticle lattice.

The main features in the optical spectra are investigated depending of the geometry and size of the nanoparticles. The results state that the spectra are more complex as the particle has less symmetry and/or has more vertexes.

Femtosecond transient absorption spectroscopic studies were conducted to investigate the electron-phonon relaxation dynamics in nanometer-sized gold and silver (Ag) particles. Simple spectral calculations were combined with two-temperature model for electron-phonon equilibration. The findings showed that strong transient bleach at the peak of the plasmon band are caused by pump-laser-induced heating and that the transient bleach signal for Ag increased after a high pump laser power. Moreover, electron-phonon coupling in small metal particles can only be obtained at low excitation levels.