The common crystalline forms available for any active pharmaceutical ingredient (API) are polymorphs or solvates. Polymorphs have same chemical entity but differ in internal crystal structure and therefore, posses different physico-chemical properties [1] [2] [3] [4] [5] . Solvates, also called as pseudo polymorphs, are crystalline adducts containing solvent molecules within the crystal structure, in either stoichiometric or non-stoichiometric proportions, giving rise to unique differences in

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... ysical and pharmaceutical properties. If the incorporated solvent is water, a solvate is termed as hydrate 6 . It has been estimated that approximately one-third of the pharmaceutically active substances are capable of forming crystalline hydrates 7 . The water because of its small size can easily fill structural voids and because of its multidirectional bonding capability, is also ideal for linking of drug molecules into stable crystal structures 8 . Crystallization plays a critical role in controlling the crystalline form and the distribution in size and shape of the drug [9] [10] [11] . A crystalline phase is created as a consequence of molecular aggregation processes in solution that lead to the formation of nuclei, which achieve a certain size during the nucleation phase to enable growth into macroscopic crystals to take place during the growth phase 6 . A perfectly ordered crystal lattice with every molecule in its expected lattice position is an ideal that is ever achieved. The other extreme is the amorphous state, in which a solid