Theory of low-energy electron diffraction for detailed structural determination of nanomaterials: Finite-size and disordered structures

Abstract

We describe how a recent efficient theory of low-energy electron diffraction (LEED) enables the determination of finite-size and disordered nanostructures. Our cluster approach, called NANOLEED, speeds up the computation to scale as $n\phantom{\rule{0.2em}{0ex}}\mathrm{log}\phantom{\rule{0.2em}{0ex}}n$, rather than the usual ${n}^{3}$ or ${n}^{2}$, with $n$ the number of atoms, for example, thereby making nanostructures accessible. To illustrate this method's capability to determine nanoscale structure, we apply it to calculate LEED intensities for Si nanowires of various lengths and thicknesses as well as for various deviations of these nanowires from the ideal Si bulk structure.