HelloWorld
Powder diffraction is a technique used to characterize polycrystalline materials. To see how the structure changes under high pressure, we squeeze the sample under x-ray radiation and see how the diffraction changes. That's high-pressure in situ X-ray diffraction.
The pressure in the sample can be determined by adding to the sample a pressure marker (e.g. ruby or salt).
In our case (unlike in the image, which is taken from Wikimedia Commons), salt was used. All that we need to do next is to find accurately the position of the highest NaCl peak on the diffraction pattern (and that's where fityk comes), calculate lattice parameter and check what pressure is corresponding for this lattice parameter for NaCl.
Using toolbar, you can with a few clicks:
- Open data file
- Choose function you want to fit
- Add the function
- Fit
Between 1. and 2. you may want to select a data range to be fitted or subtract background from the data. This can also be easily done with mouse clicking. The toolbar buttons below switch to special ''modes'' for (dis)activating data and subtracting baseline with spline.
The peak position (i.e. the peak center in the screenshot on the right) is 24.7224.