1: Introduction
The first step in structure determination by X-ray crystallography is to obtain crystals. Not just any old crystals will do. They must be of sufficient size and quality to give diffraction data to high enough resolution and with good enough counting statistics to give a satisfactory signal-to-noise ratio.
Crystal growth is sometimes portrayed as a magical, even mystical process, but there is, of course, no magic involved. The process is governed by thermodynamics and kinetics. Although rigorous training in physics is not a prerequisite to growing good crystals, it does help to have at least a qualitative understanding of the processes involved. It is also necessary to know different crystal growing techniques. A method that works well for one compound might not work at all for some other compound.
This document is divided into several parts, accessible via the links below. The next section outlines the qualities necessary for crystals to be used for structure determination by X-ray diffraction. That is followed by an overview of the physical chemistry of crystal growth and a brief description of the mechanisms by which crystal growth occurs. The level of detail given is intended to act as a qualitative introduction, rather than to be rigorously complete.
2: Crystal size, shape, and quality
3: Physical chemistry of crystal growth
4: Crystal growth mechanisms
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