Tutorials

This page provides tutorials (basic and advanced) to help GISAXS users with experiment design, data analysis, and data modeling:

Slides from Presentations

• Theory of GISAXS, Zhang Jiang (Advanced Photon Source, Argonne National Laboratory): Introduction to the theoretical methods required for correctly analyzing and modeling GISAXS data, including the DWBA and waveguide effects.
• GIXS: hands-on data analysis, Joe Strzalka (Advanced Photon Source, Argonne National Laboratory): An introduction to practical aspects of interpreting and analyzing grazing-incidence data, including the use of GIXSGUI software.
• GISAXS/GIWAXS Data Analysis: Thinking in Reciprocal-Space, Kevin Yager (National Synchrotron Light Source and Center for Functional Nanomaterials, Brookhaven National Laboratory): An introduction to the interpretation and basic analysis of GISAXS data, in particular in relation to the concept of how the experiment probes a slice through the 3D reciprocal-space.
• Synchrotron Scattering for Study of Soft Systems, Kevin Yager (National Synchrotron Light Source and Center for Functional Nanomaterials, Brookhaven National Laboratory): A brief tutorial/introduction to how x-ray scattering functions. Selected examples of using SAXS and GISAXS to study soft and hybrid systems is then presented. Finally, a few emerging methods are presented, to demonstrate how to go beyond conventional scattering approaches.
• GISAS Data Analysis with BornAgain, Walter Van Herck (Jülich Centre for Neutron Science JCNS, Germany): Description of how to use the BornAgain software for quantitatively modeling and fitting GISAXS data.
• High performance GISAXS, Alexander Hexemer (Advanced Light Source, Lawrence Berkeley National Laboratory): Description of recent developments in the high-throughput and high-performance modeling of GISAXS data, in particular describing the HipGISAXS software.

Educational

• EwaldSphere: an interactive approach to teaching the Ewald sphere construction J. Appl. Cryst. 2018 doi: 10.1107/S1600576718012876
  • Web-site with software and presentation slides for these concepts.

Courses

EPFL MOOC

A Massive Open Online Course (MOOC) from the EPFL (Ecole Polytechnique Federale de Lausanne), covering introductory aspects of synchrotron and XFEL radiation is being offered:

• https://www.edx.org/course/synchrotrons-and-x-ray-free-electron-lasers

The course begins 5th March 2018 and lasts for nine weeks. The course is aimed at a broad audience and includes the following themes:

1. Interaction of x-rays with matter;
2. The production and physics of synchrotron and XFEL radiation;
3. X-ray optics, beamlines, and instrumentation;
4. X-ray diffraction and scattering;
5. UV and x-ray spectroscopies;
6. X -ray imaging (mainly tomography and lensless imaging/ptychography);
7. Extra week on phasing techniques in macromolecular crystallography.

Frequently Asked Questions

• What are the sample/substrate requirements for GISAXS?
• How long does it take to measure a sample?
  • Do I need to worry about beam damage?
• What do I do with my data?
  • Qualitative inspection
    • Scattering features
  • Linecuts
  • Background subtraction
  • Peak Indexing
  • Modeling
  • Data Fitting
• What software is available for analysis?
• Why does sample orientation matter?
• What's that missing wedge (near qz axis) in my processed data?
• GISAXS is complicated. Why not just do microscopy?

Data Analysis

• Scattering models
• Polymer clustering or gel mesh size from SANS
• Orientation analysis (using P3HT as an example)
• Particle spacing from peak position

Scaling Analysis

• Porod plot ($\scriptstyle I\sim q^{-4}$)
• Fresnel plot ($\scriptstyle R\sim q^{-4}$)
• Kratky plot ($\scriptstyle I\sim q^{-2}$)
• Debye scaling ($\scriptstyle I\sim q^{-2}$)
• Rod-like scaling ($\scriptstyle I\sim q^{-1}$)
• Guinier plot ($\scriptstyle \ln(I)\sim 1-(R_{g}^{2}/3)q^{2}$)
• Zimm plot

Experimental Help

• GISAXS alignment
• Grating alignment

Miscellaneous Questions

• What's the difference between scattering and diffraction? SAXS and WAXS?
• Why are there oscillations below the critical angle in my reflectivity curve?

See Also

• Useful Literature
• Useful Links
• Technical articles