Instrumental broadening and the radial pair distribution function with 2D detectors
Dmitry Chernyshov1, Kenneth P Marshall1, Erlend Tiberg North2
1Swiss-Norwegian Beamlines at the European Synchrotron Radiation Facility, 38000 Grenoble, France.
Summary
This study defines the resolution function in direct space for the atomic pair distribution function (PDF). It quantifies how instrumental parameters affect PDF peak resolution, crucial for materials structure analysis.
Area of Science:
- Materials Science
- Crystallography
- Condensed Matter Physics
Background:
- The atomic pair distribution function (PDF) provides real-space structural information.
- Experimental PDFs are derived from total scattering data via Fourier transform.
- Identifying Bragg peak contributions in direct-space PDFs is challenging.
Purpose of the Study:
- To expand the definition of resolution function into direct space for X-ray diffraction.
- To mathematically develop and model the effect of instrumental parameters on PDF peak resolution.
Main Methods:
- Extended existing resolution function definitions for large-area detectors.
- Developed mathematical models for instrumental parameter effects on PDF resolution.
- Compared model predictions with experimental PDFs of LaB6 using varying capillary sizes.
Main Results:
- Successfully expanded the resolution function concept into direct space.
- Quantified the impact of instrumental parameters on PDF peak resolution.
- Validated the approach through modeling and experimental data analysis.
Conclusions:
- The developed method allows for better understanding of PDF peak resolution.
- This work aids in interpreting structural information from scattering data.
- Accurate PDF resolution analysis is vital for materials characterization.
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