Growth, spectral, mechanical, thermal and dielectric studies of undoped and rhodamine-B doped l-alanine acetate crystals

Single crystals of undoped and rhodamine-B doped l-alanine acetate have grown from solution by slow evaporation method at room temperature (30 °C). The title samples were synthesized and purified by repeated re-crystallization process. Solubility of the samples in water was found at different temperatures. The crystals were characterized by single crystal X-ray diffraction and Fourier Transform Infrared Spectroscopic (FTIR) analysis. The range and percentage of optical transmission was ascertained by recording UV–vis–NIR spectra and the optical band gap was determined. The second harmonic generation behavior of the samples was tested by Kurtz–Perry powder technique. Mechanical hardness, yield strength and stiffness constant were estimated by Vickers microhardness method. Laser damage threshold values were found out using Nd:YAG laser for the grown crystals. EDAX analysis was done to identify elements present in the undoped and rhodamine-B doped l-alanine acetate crystals. Dielectric constant and dielectric loss of the samples were estimated to understand the polarization processes and insulating behavior in the samples. TG/DTA studies were carried out to find the thermal stability and photoluminescence spectra were recorded for the samples to find the optical emission bands.