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An example of this crystallization process is the production of Glauber's salt, a crystalline form of sodium sulfate. In the diagram, where equilibrium temperature is on the x-axis and equilibrium concentration (as mass percent of solute in saturated solution) in y-axis , it is clear that sulfate solubility quickly decreases below 32.5 °C.
Crystallization of polymers is a process associated with partial alignment of their molecular chains. These chains fold together and form ordered regions called lamellae , which compose larger spheroidal structures named spherulites .
Large single crystals can be created by geological processes. For example, selenite crystals in excess of 10 m are found in the Cave of the Crystals in Naica, Mexico. [18] For more details on geological crystal formation, see above. Crystals can also be formed by biological processes, see above.
As such, powder diffraction techniques, which take diffraction patterns of samples with a large number of crystals, play an important role in structural determination. Other physical properties are also linked to crystallography. For example, the minerals in clay form small, flat, platelike structures. Clay can be easily deformed because the ...
Other methods of crystallization may be used, depending on the physical properties of the substance, including hydrothermal synthesis, sublimation, or simply solvent-based crystallization. [8] For example, a modified Kyropoulos method can be used to grow high quality 300 kg sapphire single crystals. [9]
Fractional crystallization, or crystal fractionation, is one of the most important geochemical and physical processes operating within crust and mantle of a rocky planetary body, such as the Earth. It is important in the formation of igneous rocks because it is one of the main processes of magmatic differentiation . [ 1 ]
A colloidal crystal is an ordered array of colloidal particles and fine grained materials analogous to a standard crystal whose repeating subunits are atoms or molecules. [1] A natural example of this phenomenon can be found in the gem opal, where spheres of silica assume a close-packed locally periodic structure under moderate compression.
Crystal growth is a major stage of a crystallization process, and consists of the addition of new atoms, ions, or polymer strings into the characteristic arrangement of the crystalline lattice. [ 1 ] [ 2 ] The growth typically follows an initial stage of either homogeneous or heterogeneous (surface catalyzed) nucleation , unless a "seed ...