In my bachelor`s thesis Crystalline Modification of Magnesium Carbonate and it`s Hydrates, I examined the system of crystalline modifications of magnesium carbonate and it`s hydrates. The aim of the thesis was to comprehensively study individual modifications and to investigate the relationships between their formation, stability, and transformations. I examined individual crystalline modifications and hydrates, including magnesite, hydromagnesite, nesquehonite, and lansfordite, from the perspective of synthesis, transformation, and characterisation. Special emphasis was placed on characterisation methods such as SEM, XRD, FTIR spectroscopy, and thermal analyses (TG, DTG, and DTA), which can be used to identify the characteristics of individual phases. I found that the MgO-CO$_2$-H$_2$O system, within which individual phases of magnesium carbonate form, is quite complex and that the formation of individual phases is strongly influenced by experimental conditions such as temperature, CO$_2$ partial pressure, pH, and water activity. The system comprises numerous less stable or metastable phases that can transform into more stable phases even with minor changes in conditions. Amorphous magnesium carbonate also plays an important role; although it is less stable phase, it participates in the formation and transformation into other modifications. Based on the literature review, it can be concluded that a comprehensive consideration of individual phases is essential for understanding the system of crystalline modification of magnesium carbonate and its hydrates.
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