Growth, structural, optical, thermal and dielectric properties of l-asparagine monohydrate admixtured l-thiomalic acid single crystal

Abstract

Single crystal of l-asparagine monohydrate admixtured l-thiomalic acid (LAMTM) has been grown by slow evaporation solution growth technique using water as solvent at room temperature. Single crystal X-ray diffraction analysis reveals that LAMTM crystal crystallizes by orthorhombic system with space group of P212121. The physical phase of the product was confirmed by powder X-ray diffraction analysis. The chemical composition of grown crystal was confirmed using elemental analysis. Functional groups present in the grown LAMTM crystals were identified from FTIR and FT-Raman analyses. The optical parameters, such as optical band gap energy, transparency, reflectance, refractive index were calculated using UV–vis transmittance data in the spectral range 200–800nm. Thermal stability of material is determined using TGA and DTA thermal analyses. Further the kinetic parameters, such as activation energy (E), entropy (ΔS), enthalpy (ΔH) and Gibbs free energy (ΔG), were calculated using Coats–Redfern method. The variation of dielectric properties of the grown crystals as a function of frequency has been investigated at different temperatures.