S. Vallidevi and G. Selvarajan
Abstract
Barium Chloride Thiourea Urea (BCTU) single crystals were successfully grown using a green, room temperature slow evaporation method with distilled water as a safe solvent. The transparent crystals exhibited good optical properties, with UV-Vis analysis showing a maximum absorbance at 453.8/nm. FTIR confirmed functional group interactions, and XRD indicated an orthorhombic structure. Nonlinear optical tests showed enhanced second harmonic generation (SHG) efficiency over KDP, confirming strong NLO behavior. Thermal analysis revealed stability up to 170/°C, and micro hardness tests showed increasing hardness with load. The results suggest BCTU is a sustainable and efficient NLO material suitable for photonic and optoelectronic device applications.