Optical, Mechanical and Dielectric Behavior of Urea and Thiourea Doped Lithium Sulphate Monohydrate Single Crystals

The slow evaporation method was employed to obtain single crystals of urea and thiourea-doped lithium sulphate monohydrate (LSM). The modified lattice properties of the doped LSM crystals were examined by single crystal X-ray diffraction analysis. The doped crystals showed very minimal absorption between 200 and 1200 nm in wavelength, according to studies on optical absorption. FTIR analysis was utilized to detect the existence of functional groups inside the crystal. To verify that dopants were present, EDAX analysis was performed. For doped crystals, microhardness tests were performed, and numerous types of parameters were found, including fracture toughness, brittle index, yield strength and elastic stiffness coefficient. For the doped crystals, measurements of the dielectric constant and dielectric loss were made at various temperatures and frequencies. The enhanced NLO activity of the doped crystals was verified by Kurtz and Perry’s powder method.