Influence of various metal ions on the growth and characterization of glycine polymorphs and their nonlinear optical and biological applications

Abstract

In this project, singe crystals of zinc sulphate added glycine, nickel sulphate added glycine, silver sulphate added glycine, manganese sulphate added glycine, gadolinium nitrate added glycine and lanthanum nitrate added glycine were successfully grown by spontaneous nucleation solution growth method. The grown crystals have been subjected to various characterization techniques such as Powder X-Ray Diffraction, UV-Vis, Fourier Transform Infrared (FTIR), Differential Scanning Calorimetric (DSC), Dielectric, Photoconductivity and Second Harmonic Generation studies. In addition, the grown crystals have been tested for Antibacterial and Anticancer activity studies. The polymorphic phase transformations of pure glycine crystals from and#945; polymorph to and#947; polymorph under different environmental conditions are investigated. The polymorphic phase transformations of the grown crystals are confirmed by PXRD and DSC analyses. Single crystals of 0.2, 0.4, 0.6, 0.8 and 1 M of zinc sulphate added glycine were grown by slow evaporation method. The incorporation of zinc sulphate on glycine was confirmed by the Powder X-Ray Diffraction (PXRD) and Fourier Transform Infra Red (FTIR) studies. The influence of zinc sulphate on the optical transmission in the visible and Ultraviolet (UV) region was studied by UV Visible Transmission spectrum. Differential Scanning Calorimetric (DSC) thermograms of grown and#61537; and and#947;-glycine polymorphs showed that the and#61537;- polymorph do not change its form upon heating well above the ambient temperature until its melting whereas, and#947;-glycine polymorph showed a phase transition from and#947; to and#61537;-glycine at around 211.81 °C. Low values of dielectric constant and dielectric loss of the grown and#947;-glycine crystal at high frequency range facilitated their potential application in the fields of photonics, optoelectronics and nonlinear optics. The photoconductivity study confirms the positive photoconducting nature of grown zinc sulphate added glycine crystal. Nonlinear Optical (NLO) productivity of and#947;-glycine crystals was studied by Kurtz and Perry technique using Nd: YAG laser. The results revealed increased SHG efficiency with the highest of about 3.7 in the presence of 0.6 M of ZnSO4 compared to the reference material Potassium dihydrogen orthophosphate (KDP) crystal. newline