Growth and characterization of l-lysine monohydrochloride barium nitrate single crystal for nonlinear optical applications
摘要
A well-crystalized l-lysine monohydrochloride barium nitrate (LLMBN) crystal was grown, with an ideal size of 10 mm × 8 mm × 2 mm in a time-span of 45 days. Single-crystal X-ray diffraction examinations were employed to confirm the unit cell parameters and structure of l-lysine monohydrochloride barium nitrate (LLMBN) crystal. The frequency vibrational band assignments of the LLMBN crystal were determined using Fourier transform infrared (FTIR) spectroscopy. The absorbance spectra of the grown crystal demonstrate that there is no absorption in the whole visible area, confirming the excellent optical transparency in the 200–1100 nm range, and the UV cut-off wavelength was determined to be 242 nm. Using UV–vis–NIR spectrum data, an optical bandgap (Eg = 5.29 eV) was calculated. In photoluminescence spectrum, sharp broad emission peak (570 nm) was observed, which indicate the green light emission. The thermal behavior of the grown crystal was investigated using thermogravimetry and differential thermal analysis (TG/DTA). A vickers microhardness test was performed to determine the mechanical stability of the grown crystal. The dielectric permittivity and loss as a function of frequency were measured for the grown crystal. A photoconductivity test demonstrates that the grown crystal has a negative photoconductive character. Surface micrographs of the as-grown crystal and the presence of metal ions were confirmed using SEM/EDAX analysis. LLMBN crystal was subjected to analyses nonlinear optical studies of second- and third-order harmonic generation.