Simulation of Surface Resonant X-ray Diffraction.

Area of Science:

• Materials Science
• Surface Science
• Computational Physics

Background:

• Surface resonant X-ray diffraction is a powerful technique for probing atomic structures at surfaces.
• Accurate simulation of these experiments is crucial for interpreting complex experimental data.

Purpose of the Study:

• To develop an ab initio numerical tool for simulating surface resonant X-ray diffraction experiments.
• To calculate crystal truncation rods and spectra around X-ray absorption edges.
• To account for experimental parameters like sample geometry and beam conditions.

Main Methods:

• Utilizing density functional theory (DFT) to determine atomic resonant scattering factors.
• Calculating diffraction peak intensities for surfaces with thin films or adsorbed layers.
• Creating a numerical diffractometer to mimic experimental operation modes.

Main Results:

• The tool successfully calculates crystal truncation rods and spectra at any reciprocal space position.
• Simulations incorporate sample geometry, beam polarization, and incidence/exit angles.
• Validation through case studies of a magnetite thin film and adsorbed bromine on copper.

Conclusions:

• The developed numerical tool provides accurate simulations for surface resonant X-ray diffraction.
• This tool aids in the analysis of thin films and adsorbed layers.
• It facilitates comparison between theoretical predictions and experimental spectra.