X-ray structure factors for Si nanoparticles

We examine the structural change of Si nanocrystals as a function of size. We present calculated x-ray structure factors over the range of 1-6 nm. We examined how the scattering evolves from broad to sharp features as the particle size increases. The transition from molecular-like broad unresolved features to polycrystalline-like resolved peaks can be set at similar to2.15 nm. The scattering change due to surface dimer relaxation, which has been proposed as the basic mechanism of the acquired optical characteristics, is examined. (C) 2004 American Institute of Physics.