X-ray powder diffraction is a method based on the scattering of electromagnetic waves by electrons in an atom. It is used to identify crystalline solids and phases in a sample, to determine the microstructural properties of the sample and crystal structures. Each crystalline substance gives a powder diagram that allows us to perform qualitative analysis.
The main purpose of the tasks was to determine the presence of different crystalline phases, based on the comparison of powder images of the sample and the standards from the database.
In my task, I analysed ten samples of various decorative cosmetic products. I was interested in the differences between products from different manufacturers and shades of colour, the content of crystalline substances in the sample itself, and the presence of substances that may not be listed on the declaration. I prepared the samples properly before recording and then analysed them using computer programs by comparing their diffractograms with the diffractograms of the standards in the database. I found that the diffraction grams of some cosmetics are very similar, suggesting a similar composition of the samples. In some samples, I have not been able to identify all the deflection peaks, as some substances are present in the sample in very small amounts and consequently, we cannot say with certainty that the peaks belong to a specific substance.
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