Scherrer Formula and interpreting values

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In summary, the conversation is about a MATLAB script that can detect peaks and find FWHM of detected peaks from data. The results are reliable, but the crystallite sizes are slightly different from a previously used online calculator. The OP has made all necessary conversions and adjustments, but lacks the crystallography background to fully interpret the data. They are seeking advice on how to ensure the accuracy of the values and mention the availability of freeware and resources for determining grain size.
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erbilsilik
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I have developed a script in MATLAB that can detect peaks from datas and that can find FWHM of detected peaks. Scripts gives reliable results but crystallites sizes are different a little from this http://mahendrakoppolu.blogspot.com.tr/2013/07/online-crystallite-size-calculator.html

Link to my data: http://pastebin.com/Ut9YgKGs

Generated physical properties from MATLAB: http://pastebin.com/K0uEZ6Mr

I made all conversion, degree to rad. The problem is that I don't have enough crystallography background to interpret the data. So how can I be sure from the values?

Check also this if you are interested in script.
 
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  • #2
erbilsilik said:
I have developed a script in MATLAB that can detect peaks from datas and that can find FWHM of detected peaks. Scripts gives reliable results but crystallites sizes are different a little from this http://mahendrakoppolu.blogspot.com.tr/2013/07/online-crystallite-size-calculator.html

Link to my data: http://pastebin.com/Ut9YgKGs

Generated physical properties from MATLAB: http://pastebin.com/K0uEZ6Mr

I made all conversion, degree to rad. The problem is that I don't have enough crystallography background to interpret the data. So how can I be sure from the values?

Check also this if you are interested in script.
Dear OP.
The difference between the calculator and your determination can be:
1. Strain/stress peak broadening.
2. Orientation.
3. grain geometry.
4. Superposition of different phases.
5. Non-Gaussian peak profile.
6. Different geometric constant.
7. Improper baseline subtraction.
8. Improper internal shift corrections.
9. Different instrumental broadening.

In case you are interested please refer to Retrieved mailing list.
There is freeware available that can help in determinate grain size like Fityk.
You can visit also CCP14 (sends for computational crystallography) where you can accesses to many software, shareware, freewares and applications.

Goodluck
 

FAQ: Scherrer Formula and interpreting values

What is the Scherrer Formula and what does it measure?

The Scherrer Formula is a mathematical equation used to determine the average size of crystalline particles in a sample. It measures the width of a diffraction peak in an X-ray diffraction pattern, which is directly related to the size of the crystal.

How is the Scherrer Formula calculated?

The Scherrer Formula is calculated using the equation D = Kλ/βcosθ, where D is the average crystal size, K is a constant (typically between 0.9 and 1), λ is the wavelength of the X-rays, β is the full width at half maximum (FWHM) of the diffraction peak, and θ is the diffraction angle.

What are the units of the values used in the Scherrer Formula?

The units of the values used in the Scherrer Formula are as follows: D is typically measured in nanometers (nm), K is dimensionless, λ is measured in angstroms (Å), β is measured in radians (rad), and θ is measured in degrees (°).

What factors can affect the accuracy of the Scherrer Formula?

Several factors can affect the accuracy of the Scherrer Formula, including the quality of the X-ray diffraction pattern, the degree of crystallinity of the sample, and the presence of any preferred orientations in the crystal lattice. Additionally, the choice of K value and the accuracy of the diffraction angle measurement can also impact the results.

Can the Scherrer Formula be used for all types of crystalline materials?

The Scherrer Formula is most accurate for materials with well-defined, isotropic crystal structures. However, it can still provide useful estimates for less ideal materials, as long as the limitations and potential sources of error are taken into consideration. It is not applicable for non-crystalline materials such as glasses or liquids.

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