Investigations on Growth and Characterization of Undoped and Thiourea-Doped γ-Glycine Crystals for NLO Applications

Abstract

Pure (undoped) and thiourea-doped γ-glycine salts were synthesized by the solution method, and they were subjected to solubility studies in the temperature range of 30–50°C. Using the solubility data, the saturated solutions of the synthesized salts were prepared, and single crystals of undoped and thiourea-doped γ-glycine were grown from aqueous solution by the slow evaporation solution technique (SEST). Single crystal X-ray diffraction (XRD) and powder XRD studies were carried out to ascertain the crystal structure, and it is observed that the grown crystals crystallize in hexagonal structure. UV-visible transmittance spectra were recorded for the samples to analyze the transparency of the grown crystals. Nonlinear optical (NLO) activity for the grown crystals has been confirmed by measuring the Second Harmonic Generation (SHG) efficiency using a Nd:YAG laser. The density of the grown crystals was measured. Also, microhardness studies, thermogravimetric and differential thermal analyses (TG/DTA), and dielectric studies have been carried out to characterize the grown pure and thiourea-doped γ-glycine crystals. The obtained results are presented and discussed.

Keywords:

• Characterization
• Density
• Dielectric
• Dopant
• Experimentation
• Growth
• Laser
• Microhardness
• Properties
• Synthesis
• UV-visible
• XRD

ACKNOWLEDGMENTS

The authors would like to thank the staff members of M. K. University, Madurai, Crescent Engineering College, Chennai, and IIT, Chennai, for the help rendered to carry out this work. We also thank authorities of Aditanar College of Arts and Science, Tiruchendur, and S. T. Hindu College, Nagercoil, for the encouragement given to us to carry out the research work.