How to best approach atomic substitutions in Rietveld refinement?
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When approaching atomic substitutions in Rietveld refinement, it is crucial to consider the structural changes induced by the substitution process. Studies have shown that substitutions, such as Sr2+ for Ca2+ in ye'elimite or Sr for Ca in hydroxyl potassium-richterite, lead to significant alterations in crystal systems. The refinement process involves quantifying the substitution rate by analyzing occupancy sites affected by the substitution and evaluating the evolution of atomic coordinates, interatomic distances, and bond angles. Additionally, the refinement method should aim to preserve the structure of the semantic object being refined and ensure compositional operations at the semantic level. By following these guidelines and utilizing Rietveld refinement techniques, researchers can effectively study and understand the impact of atomic substitutions on crystal structures.
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| Papers (4) | Insight |
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14 Citations | In Rietveld refinement, carefully consider crystal structures when refining Sr-bearing ye'elimite, incorporating both orthorhombic and cubic structures, while for Ba-bearing ye'elimite, focus on the cubic structure. |
Open access•Journal Article 23 Citations | Not addressed in the paper. |
5 Citations | In Rietveld refinement, quantify atomic substitutions by refining occupancy sites affected by the substitution, as shown in the study on phosphostrontium carbonate hydroxyapatites. |
| The paper focuses on atomic refinement in process description languages through compositional operations, preserving structure, and using semantic objects to make behavior atomic. |
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