Method FW1/4/5M of full Grain Size Distribution Determination


Check also:
Nanopowder XRD Processor Demo


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:

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 full diffraction theory involved and credits please refer to:
"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, Roman Pielaszek (pielasze@unipress.waw.pl), 2003 (see in PDF)


Grain Size Distribution Calculator
Please note that FW1/5M > FW4/5M (otherwise result '!!' will be seen)
1. FW1/5M: Å-1    FW4/5M: Å-1   ===>   <R>=??Å    σ=??Å    <R>/σ=??
2. FW1/5M: Å-1    FW4/5M: Å-1   ===>   <R>=??Å    σ=??Å    <R>/σ=??
3. FW1/5M: Å-1    FW4/5M: Å-1   ===>   <R>=??Å    σ=??Å    <R>/σ=??
4. FW1/5M: Å-1    FW4/5M: Å-1   ===>   <R>=??Å    σ=??Å    <R>/σ=??
5. FW1/5M: Å-1    FW4/5M: Å-1   ===>   <R>=??Å    σ=??Å    <R>/σ=??
6. FW1/5M: Å-1    FW4/5M: Å-1   ===>   <R>=??Å    σ=??Å    <R>/σ=??

Pearson VII Grain Size Distribution Calculator
1. a2:     a3:   ===>   <R> = ?? Å    σ = ?? Å    <R>/σ = ??    FWHM = ?? Å-1
2. a2:     a3:   ===>   <R> = ?? Å    σ = ?? Å    <R>/σ = ??    FWHM = ?? Å-1
3. a2:     a3:   ===>   <R> = ?? Å    σ = ?? Å    <R>/σ = ??    FWHM = ?? Å-1
4. a2:     a3:   ===>   <R> = ?? Å    σ = ?? Å    <R>/σ = ??    FWHM = ?? Å-1
5. a2:     a3:   ===>   <R> = ?? Å    σ = ?? Å    <R>/σ = ??    FWHM = ?? Å-1
6. a2:     a3:   ===>   <R> = ?? Å    σ = ?? Å    <R>/σ = ??    FWHM = ?? Å-1

Grain Size Distribution Plotter
In order to obtain normalized distribution, fractions must be normalized
1. <R>: Å3    σ: Å    fraction: a.u.
2. <R>: Å3    σ: Å    fraction: a.u.
3. <R>: Å3    σ: Å    fraction: a.u.
4. <R>: Å3    σ: Å    fraction: a.u.
5. <R>: Å3    σ: Å    fraction: a.u.
6. <R>: Å3    σ: Å    fraction: a.u.
Output curve units:

<R> error estimation
Peak intensities shall be expressed in counts (net height of the peak).
1.     Peak height:  counts   ===>   ERR<R> = ?? %
2.     Peak height:  counts   ===>   ERR<R> = ?? %
3.     Peak height:  counts   ===>   ERR<R> = ?? %
4.     Peak height:  counts   ===>   ERR<R> = ?? %
5.     Peak height:  counts   ===>   ERR<R> = ?? %
6.     Peak height:  counts   ===>   ERR<R> = ?? %

Lattice constant error estimation
Peak intensities shall be expressed in counts (net height of the peak).
1.     Peak height:  counts    Grain size:  nm    Two-theta:  deg    Wavelength:  Å   ===>   ERR<d> = ?? %
2.     Peak height:  counts    Grain size:  nm    Two-theta:  deg    Wavelength:  Å   ===>   ERR<d> = ?? %
3.     Peak height:  counts    Grain size:  nm    Two-theta:  deg    Wavelength:  Å   ===>   ERR<d> = ?? %
4.     Peak height:  counts    Grain size:  nm    Two-theta:  deg    Wavelength:  Å   ===>   ERR<d> = ?? %
5.     Peak height:  counts    Grain size:  nm    Two-theta:  deg    Wavelength:  Å   ===>   ERR<d> = ?? %
6.     Peak height:  counts    Grain size:  nm    Two-theta:  deg    Wavelength:  Å   ===>   ERR<d> = ?? %