X-ray crystallography is the most successful methods for determining the structure of macromolecules. However, obtaining crystals of macromolecules is a very challenging task. The crystallization process can be considered as a two-stage experiment, where the first stage determines chemical and physical conditions under which the sample tends to crystallize, while the second stage refines the parameters to produce crystals suitable for analysis by X-ray diffraction. The quality and ease of X-ray structure determination is directly correlated with the size and the perfection of the crystalline samples. Initial crystals are frequently microcrystals or clusters which often have unfavorable morphologies or sizes, yielding poor diffraction intensities. It is therefore generally necessary to improve upon these initial conditions in order to obtain better crystals of sufficient quality for X-ray data collection.
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