Module 5 : Modern Characterization of materials

Lecture 32: Powder X - ray diffraction

You can use XRD to determine

• Phase Composition of a Sample

–Quantitative Phase Analysis: determine the relative amounts of phases in a mixture by referencing the relative peak intensities

• Unit cell lattice parameters and Bravais lattice symmetry

–Index peak positions

–Lattice parameters can vary as a function of, and therefore give you information about, alloying, doping, solid solutions, strains, etc.

• Residual Strain (macrostrain)

• Crystal Structure

–By Rietveld refinement of the entire diffraction pattern

• Epitaxy/Texture/Orientation

• Crystallite Size and Microstrain

–Indicated by peak broadening

–Other defects (stacking faults, etc.) can be measured by analysis of peak shapes and peak width

We have in-situ capabilities, too (evaluate all properties above as a function of time, temperature, and gas environment)