Figure 3. Final Rietveld refinement of the HAp sample: calculated (black solid line), experimental (red dots mark) X-ray powder diffraction pattern and difference curve (blue)

From

Rietveld Refinement of the Crystal Structure of Hydroxyapatite Using X-ray Powder Diffraction

A. El Yacoubi, A. Massit, S. El Moutaoikel, A. Rezzouk, B. Chafik El Idrissi

American Journal of Materials Science and Engineering. 2017, 5(1), 1-5 doi:10.12691/ajmse-5-1-1