The Difference between Plasmon Excitations in Chemically Heterogeneous Gold and Silver Atomic Clusters

Area of Science:

• Computational Nanoscience
• Plasmonics
• Materials Science

Background:

• Doping nanoparticles affects plasmon peaks, but mechanisms are unclear.
• Understanding doping effects is crucial for nanostructure applications.

Purpose of the Study:

• Investigate how Pd or Pt doping affects plasmon peaks in Au and Ag atomic arrays.
• Elucidate the microscopic mechanisms behind observed plasmon peak evolution.

Main Methods:

• Time-dependent density functional theory (TD-DFT) calculations.
• Analysis of excitation properties and electronic structure.
• Electron transfer analysis.

Main Results:

• Pd/Pt doping broadened and shifted plasmon peaks in 10x2 Au/Ag arrays.
• Pd doping of Au arrays caused blueshifts; Pt doping caused redshifts.
• Pt doping of Ag arrays caused significant redshifts and broadening.

Conclusions:

• Doping responses depend on d-electron energy levels and orbital positions.
• Altered orbital symmetry and gap size influence plasmon excitation.
• Electron transfer correlates with excitation energy, validating the analysis method.