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Chapter II Solution Growth….
Δ C =C – C * and σ = Δ C /C * = S – 1
2.5 Solubility Curve and Its Importance
Depending upon the type of compound to be crystallized, two broad
categories of growth are normally used; which are (i) low temperature
aqueous solution growth and (ii) high temperature and high pressure
hydrothermal growth.
For any solution growth experiment it is required to study the
temperature-concentration (T-C) diagram or the solubility curve. Figure (2.6)
depicts the typical diagram of T-C curve, where the solubility of the test
substance increases with temperature. The solubility curve in solid line divides
the diagram into two major regions; that of under saturated solutions below the
saturation curve and that of supersaturated solutions above the curve. Usually,
the region of super saturated solution is divided into a meta-stable and labile
zone. The meta-stable region is formed because energy must be spent on the
formation of a critical size crystal nucleus. Labile solutions are unstable,
strongly supersaturated solutions in which the
Figure:2.6 Typical T-C curve.
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