Powder Diffraction - Spallation Neutron Source

Hugo Rietveld’s technique
Hugo Rietveld realized that if a pattern could be modeled, the fit
between a computed pattern and observed data could be optimized.
– Similar to single-crystal diffraction, except that now “experiment dependent
parameters” must now be fit as well.
• Background
• Peak broadening
• Lattice constants
– Must have approximate model to start
– Fewer data are available (usually)
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