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 ∼2.15 nm. The scattering change due to surface dimer relaxation, which has been proposed as the basic mechanism of the acquired optical characteristics, is examined.