Effect of NaCl on the properties of sulphamic acid single crystals.

Single crystals of pure and NaCl doped sulphamic acid (SA) were grown by slow evaporation method at room temperature. The lattice parameters and structure were determined by using single crystal and powder X-ray diffraction analyses. The presence of dopant in the SA lattice was affirmed by EDAX analysis. UV-Vis spectra show maximum transmittance in the visible region. The band gap energies were found to be 6.06 eV and 5.70 eV for pure and NaCl doped SA crystals respectively. From the PL specta the emission were observed at 335 and 424 nm for pure and 340 and 428 nm for doped SA crystal. The thermal stability of the grown crystals were analyzed by thermogravimetric and differential thermal analysis (TGA/DTA) and revealed that the grown crystals were thermally stable up to 331 °C and 334 °C for pure and NaCl doped SA. Vickers microhardness study reveals that the hardness of the crystals is increase with increasing load. The photoconductivity study shows that the grown crystals are negative photoconductive nature. The Laser Damage Threshold (LDT) indicates the grown crystals have good resistance to laser radiation than a standard Potassium dihydrogen phosphate (KDP) crystal. The Z-scan technique was employed to determine the nonlinear refractive index, nonlinear optical absorption and third order nonlinear optical (TONLO) susceptibility of the grown crystals using He-Ne laser.