Lecture

The Rietveld method: Phase Analysis and Structure Refinement

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Description

This lecture introduces the Rietveld method, a technique for diffraction pattern analysis and structure refinement. It covers phase identification, crystal structure determination, quantitative phase analysis, and microstructural analyses. The method involves iterative least-squares minimization between observed and calculated diffraction profiles, extending to XRD profiles. The lecture explains how to determine crystal structures, phase concentrations, and other sample characteristics using the Rietveld method. It also discusses the criteria for a good fit, including visual inspection, numerical factors, and monitoring of chemical parameters. Examples of simple fitting scenarios with mixtures of rutile and alite are presented, demonstrating the refinement of lattice parameters and atomic displacement factors.

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