Polymorphism is the unique phenomenon by which a pure chemical compound can exist in more than one structural orientation, with different physical characteristics. This mere existence of disparity in physical properties among the polymorphs of the same material prompts the main essentiality to control and isolate the polymorphs at the level of nucleation for specified applications. In this regard, a thorough knowledge of the nucleation behavior of the polymorphs at different environmental circumstances is highly essential. Glycine, the organic molecule exists in three different polymorphic forms α, β and γ at ambient conditions. Existence of these three polymorphs is due to the difference in the stacking of the molecules which exist in the zwitterionic form in aqueous solution. This difference in stacking is mainly due of the lack or excess of certain electrostatic forces between the ionic charges in the solution. This deficiency of the necessary energy to withstand as a single molecule leads the molecular species in the solution to depend on their neighboring molecules for such charge compensation to ensure their stability and this is known as self-charge compensation. They pack as parallel dimers bilayer which is the preferable configuration of α polymorph and leads to their spontaneous nucleation in the solution. These bilayers are formed by strong NH….O hydrogen bonding interactions between cyclic hydrogen bonded zwitterionic dimers and these bilayers are packed by van der Waals interactions. When certain external force / parameters can overcome this situation then a good control over the nucleation behavior can be achieved. This deficient energy when supplied by some external force leads to a way to alter the configuration of molecules in the solution. This external force / parameter must be capable of overcoming the huge barrier / activation energy that prevents the singular existence of molecules with at most stability. This would finally lead to the monomeric existence of molecules in the solution which favors the β and γ forms of glycine. In the γ polymorph the dominating feature of the intermolecular packing is the hydrogen bonding between amino nitrogen and carboxyl oxygen atoms which links the molecule into helical chains about the threefold screw axis parallel to the c-axis. These chains are packed by lateral hydrogen bonding of monomers forming a three dimensional network of hydrogen bonds. In this paper the external forces are chosen to be sodium nitrate and sodium hydroxide. The nucleation behavior of the α and γ polymorphs of glycine in the presence of these two induced charge compensators has been investigated and explained based on the concept of charge compensation mechanism. This concept explains the mechanism behind the nucleation of polymorphs in the presence of sufficient externally added charged species which induce the required nucleation through charge compensation. In-situ micro droplet evaporation as well as slow evaporation has been applied as the appropriate methods to carry on this investigation. The induced charge compensators sodium nitrate (ICCsn) in the concentration range from 0.16 to 13.07 mole% and sodium hydroxide (ICCsh) in the concentration range from 0.13 to 3.19 mole% were used for these experiments. The added externally charged ions overcome the self-charge compensation and this is presented evidently through the variation in solubility, pH, polymorphic nucleation and morphology of the nucleated polymorphs. The solubility of glycine aqueous solution increases from 34.68 to 101.03 g/100ml with ICCsn concentration and from 33.10 to 88.19 g/100ml with ICCsh concentration. This in turn alters the supersaturation of the solution which increases from 0.33 to 2.89 with ICCsn and from 0.02 to 1.73 with ICCsh concentrations. The pH increases from 6.05 to 6.99 and from 7.95 to 10.47 with ICCsn and ICCsh concentrations respectively. The ionic strength of the solution increases from 131.25 to 205.17 and from 127.19 to 169.91 mol L^-1 with ICCsn and ICCsh concentrations. In the case of sodium nitrate, 100%α is observed up to 5.52 mole %. At the next concentration of 6.26 mole% γ nucleation appears with theα form. With further increase in the concentration of ICCsn the number of α decreases from 100 to 1% and γ increases from 17 to 99% at the final concentration of 13.07 mole %. In the case of sodium hydroxide, 100% α is observed up to 0.27 mole% and at the next concentration of 0.34 mole% γ appears along with the α form. With further increase in ICCsh concentration, the number of α decreases and γ increases. This proportionate appearance of the nucleated polymorphs shows that the self-charge compensation which was dominant up to 5.52 mole % in case of ICCsn and up to 0.27 mole % in case of ICCsh is overcome by induced charge compensation of additive ions at 6.26 mole% and 0.34 mole% respectively. The form of crystallization and the proportionate appearance of the nucleated polymorphs are confirmed by powder x-ray diffraction.

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