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Chapter II Solution Growth….
Details of kinetics and thermodynamics of nucleation are discussed by
many authors [26,88-91].
2.20 Induction Period
When a supersaturated condition is achieved, the embryos are formed
by single molecular addition starting from the monomer at the beginning. Thus
it takes sometime for the formation of critical nucleus from the monomers. The
time taken between the achievement of super-saturation or super-cooling and
the appearance of crystal nucleus in a supersaturated system is known as the
induction period.
The methods of induction period measurements are:
(1) Conductivity method
(2) Turbidity method
(3) Dilatometer method
(4) Visual observation method
Depending upon solubility of material one can choose appropriate technique
available for determination of induction period. For example, if materials have
low solubility, the conductivity and turbidity methods are suitable; on the other
hand, for materials having high solubility, dilatometer and direct vision
methods are used. These have been discussed extensively by several
authors [92-96].
As the present author has used visual observation method, a detailed
discussion of other methods has been avoided.
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