# XRD data: particle size, cell size etc

1. Jun 26, 2009

### Oxygenne

I use to do XRD from room temperature to High temperature and then cooling again at room temperature.
I see there is constant going to the right for all the peaks and also their intensities are decreasing, also the width of peaks is becoming larger.
I would like to interpret those data and also to calculate the particle size and the unit cell size (if there is a change with the temperature).
It seems the phase is not change only the garbages and the intensities values.
Could you help me to interpret those data or to guide to read something on the web to help me with this?
Thank you!

Last edited: Jun 26, 2009
2. Jun 29, 2009

### drizzle

Last edited by a moderator: Apr 24, 2017
3. Jun 30, 2009

### Oxygenne

Thank you drizzle!
On an Intensity vs. 2*theta plot of a powdered, crystalline sample how to calculate the miller indices?

4. Jul 1, 2009

### drizzle

I think to determine the miller indices of each peak [the surface where the diffraction occur] you would need to use GPDS cards or a handbook [it’s a catalogue that holds the analyzed XRD data of almost all structures and compounds, will maybe not all, it depends on the book]. it goes like this; in your XRD pattern you would see several peaks, each at a precise angle. say that your XRD pattern is of the material ZnO and the first peak is at 35 degrees, you then should look for ZnO in that data and find the matched angle thus the corresponding surface, you would find tables of different data, i.e.

XRD pattern for ZnO:

(hkl) 2θ relative intensity
100 35° 87.5
102 47° 63
etc

also it could be calculated.

5. Jul 1, 2009

### Oxygenne

I would like to calculate taking in account the data I have (Intensity vs. 2*theta plot)

I found a formula but there is included the unit cells parameters and I do not want to use that, because my goal is to find the unit cell parameter using the recorded data for each set of data.

* How to interpret the constant moving of my intensities to the right with each temperature step?

*How to interpret the constant decreasing in intensity of every peak with each temperature step?

Thank you!

Last edited: Jul 1, 2009