Method FW1/4/5M of full Grain Size Distribution Determination
Method FW1/4/5M allows for quick Grain Size Distribution (GSD) calculation.
You need to specify two peak widths: measured at 1/5 and 4/5 of maximum of
the diffraction peak (FW1/5M and FW4/5M, respectively).
The metod takes into account only size-broadening of the diffraction maxima.
Therefore the following phenomena are not considered:
- stacking faults
- lattice strain
- lattice defects
- experimental broadening.
The method in the most basic form (as presented here) is accurate for nanocrystals
of size not greater than 200-300Å (no corrections are required in this range).
Peak widths are expected to be given in scattering vector q=4πsin(θ)/λ
units (hence standard 2θ diffraction data must be scaled accordingly).
You may convert your standard two-theta data using on-line converter.
For usage details please consult manual either in HTML
or PDF form.
For credits and diffraction theory involved please refer to:
-
R.Pielaszek "Analytical expression for diffraction line profile for polydispersive powders",
Applied Crystallography, Proceedings of the XIX Conference, World Scientific, pp.43-50
-
R.Pielaszek "FW15/45M method for determination of the grain size distribution from powder diffraction line profile",
Journal of alloys and compounds, 392, pp. 128-132
-
R.Pielaszek "Nanodyfrakcja rentgenowska" (a book, on-line translation available),
ISBN: 83-89585-47-2, PDF version here [PL]
-
R.Pielaszek "Dyfrakcyjne badania mikrostruktury nanokryształów poddawanych działaniu
wysokiego ciśnienia" (eng."Diffraction studies of microstructure of
nanocrystals exposed to high pressure"),
PhD. Thesis University of Warsaw, Department of Physics,
2003 (see in PDF)