Nanoscale size effects on the plasmon response of diamond powder

Abstract

Parallel electron-energy-loss spectroscopy was used previously to obtain low-loss spectra for nanocrystalline diamond powder for three particle sizes of approximate diameters, 3, 5 and 8nm by Bursill, Peng and Prawer (1997, Phil. Mag. A, 76, 769). These experimental results are now compared with theoretical results for small spherical particles. Perturbation theory is used to explain how the peak positions and intensities of the surface and volume plasmon are related to the particle size. The effects of surface layers of amorphous diamond-like material are included in this theory; these may also influence peak positions and peak intensities. Good agreement is obtained with the experimental results, within certain limitations, which concern both the experimental results and the theory.