Investigation of growth, optical, thermal, mechanical, electrical, laser damage threshold properties of 1, 2, 3-Benzotriazolium Dihydrogen Phosphate (BTDHP) single crystal for nonlinear optical (NLO) applications

The 1, 2, 3- benzotrizolium dihydrogen phosphate (BTDHP) single crystal was grown at ambient temperature with methanol as a solvent using the conventional slow evaporation solution method. The BTDHP crystalline material was structurally confirmed by single crystal X-ray diffraction (SXRD) study and it revealed that the crystal has triclinic structure and P-1 space group. Powder X-ray diffraction (PXRD) was recorded to find various (h k l) planes, and the obtained peaks were compared with CIF data. UV- Visible-NIR spectroscopy helped to study optical properties of BTDHP crystal. High-Resolution X-ray diffraction (HRXRD) has determined the crystalline perfection of the present material. The vibrational assignments in the grown crystal were found using Fourier transform infrared (FTIR) spectroscopy. The thermal stability of BTDHP crystal was found to be upto 181 °C and the different levels of decomposition temperatures were analysed using thermogravimetric differential thermal analysis (TG–DTA). The laser damage threshold (LDT) value of BTDHP crystal was recorded to be 10.2 GW/cm 2 which is favourable for laser applications. The photoconductivity measurements revealed that the crystal has a positive photoconductive nature. The chemical etching was investigated to calculate the etch pit density. The dielectric experiment (constant& loss) was performed for BTDHP crystal as a function of frequency at ambient temperature to measure electrical properties of the material. The mechanical stability of the grown BTDHP crystal was studied using Vickers microhardness measurement. The third-order non-linear susceptibility was measured and analysed by Z-scan technique using (He–Ne) laser of wavelength 632.8 nm.