IJSRSET151636 | Received: 05 December 2015 | Accepted: 11 December 2015 | November-December 2015 [(1)6: 203-208] © 2015 IJSRSET | Volume 1 | Issue 6 | Print ISSN : 2395-1990 | Online ISSN : 2394-4099 Themed Section: Science and Technology 203 Experimental Determination of Metastable Zone Width, Induction Period, Interfacial Energy, Growth and SHG Efficiency of N-[(propan-2-ylidene) amino] Thiourea G.V.Pandian*, I. John David Ebenezar, P. Anbusrinivasan Department of Chemistry, T. B. M. L. College, Porayar, Tamilnadu, India ABSTRACT N-[(propan-2-ylidene) amino] thiourea an organic crystal which is grown by solution growth technique by adopting slow evaporation method from the solvent methanol.Nucleation parameters such as metastable zone width, induction period and interfacial energy have been determined for N-[(propan-2-ylidene) amino] thiourea single crystals. The induction period was measured at various super saturations and hence the interfacial energies were evaluated. Using the interfacial tension value, the nucleation parameters such as radius of the critical nuclei(r*), the Gibbs free energy for the formation of a critical nucleus (ΔG*) and the number of molecules in the critical nucleus (i*) were also calculated for methanol at two different temperatures. The effect of surface tension, viscosity and density of these solvents are correlated with interfacial tension. FT-IR studies confirm the structure and presence of functional groups in the grown crystals. The optical transparency was examined by UV-Spectral analysis. The grown crystal was examined by X-ray diffraction to determine its crystalline nature. Second harmonic generation efficiency of the powdered N-[(propan-2-ylidene) amino] thioureawas tested using Nd:YAG laser and it is found to be 1.8 times that of potassium dihydrogen phosphate. Keywords: Nucleation, induction period, Solubility, SHG efficiency I. INTRODUCTION In recent days the field of opto electronics, optic communication have experienced tremendous advancements. The research on new organic nonlinear optical materials has attracted more research groups to them for their advantages over the inorganic nonlinear optical materials. The organic nonlinear optical molecules are widely used in many applications such as optical communication, information storage, and optical switching [1-5]. In recent days organic molecular crystals are direct imparting attention due to large optical property, bulk in size, hard and stable. Due to these properties, these crystals are needed in many electronic devices like colour displays and optical memories. From this background, it is needed to search organic crystals with optical property. Generally, recent researches have mentioned that organic crystals are bulk in size, hard, stable, and large Nonlinear optical susceptibilities compared to the inorganic crystals but they have poor mechanical properties. Considering all these parameters the modern scientists have concentrated on the growth of organic crystals. In addition thiosemicarbazone molecules containing π- electron conjugation system asymmetrized by the electron donor and acceptor groups are highly polarizable entities for NLO applications. Hence the N- [(propan-2-ylidene) amino] thiourea is the one of the potential organic optical materials. Which belongs to the carbonyl group of compounds .The Ketone group is asymmetrical (Chiral carbon). Therefore in the present studieswe report on the induction period, nucleation parameters and SHG efficiency of organic optical N-[(propan-2-ylidene) amino] thioureacrystals by slow evaporation solution growth technique (SESGT) [6-16]. Metastable zone width is an essential parameter for the growth of good crystals from solution. Because it is the direct measure of the stability of the solution in its saturated region. The