Growth, spectral, optical, and third harmonic generation studies of p-Hydroxyacetanilide (PHA) crystals

An organic p-Hydroxyacetanilide (PHA) crystal was grown using the slow evaporation technique. The PHA crystal crystallized in the monoclinic crystal system with centrosymmetric space group P21/a. The functional groups in the crystal were identified using Fourier-transform infrared and Raman spectroscopy analyses. The crystallization quality of the PHA crystal was investigated using the high-resolution X-ray diffraction technique. In addition, the linear optical properties of the crystal were discerned using UV–Vis–NIR spectroscopy. Maximum absorption in the ultraviolet region and low absorbance in the visible region were observed for the crystal. The cut-off wavelength for the crystal was observed at 318 nm, which substantiated its utilization for optoelectronic device applications. The refractive index of the crystal was determined to be 1.53. Further, the crystal was excited at 300 nm and emission spectra were recorded using photoluminescence spectroscopy. Violet fluorescence peak was observed at 330 nm. Laser damage threshold (LDT) analysis was performed to identify the limit of performance of the crystal. The LDT value for the PHA crystal was calculated to be 23.7 GW/cm2, which is higher than those of standard nonlinear optical materials. The third-order NLO properties of PHA crystal were investigated using the Z-scan technique. The optical nonlinear susceptibility and nonlinear refractive index values of the crystal were 2.846 10−4 esu, and 5.250 10−7, respectively. The results of this study corroborate the applications of the crystal in optoelectronics field.