Insight on the growth, mechanical, optical and thermal studies of pyrrolidinium 2-carboxy 6-nitrophthalate (PY3N) single crystal-An effective third-order nonlinear optical material for optical limiting applications

A new interesting third-order nonlinear (NLO) organic material Pyrrolidinium 3-nitrophthalate (PY3N) is synthesized by water solvent in an equimolar ratio by room temperature solution growth technique. The crystal system (monoclinic), space group (P2(1)/c and lattice constants (a = 13.245 (9) angstrom, b = 11.775 (7) angstrom, c = 8.612 (5) angstrom, beta = 99.265 (2)degrees) were obtained from single crystal XRD. The vibrational and NMR spectral analyses confirmed the different functional groups and chemical environment of molecules present in the crystal lattice. The UV-vis study showed the crystal has good transparency with band gap and the index of refraction displays the normal dispersion behavior. The crystal demonstrates moderate surface tolerance to laser power (4.887 GW cm(-2)). The non-linear parameters were estimated by Z-scan technique. We have investigated the second order hyperpolariz- ability 'gamma' of PY3N crystal with electric field and frequency by using HF method with 6-311++g(d, p) level. The theoretical third order susceptibility chi((3)) value is 0.196 x 10(-6) esu. The experimental chi((3)) value is 3.131 x 10(-6) esu. The effective optical limiting action is directed by PY3N crystal. The crystal is identified as a soft material from hardness measurement. The PY3N crystal has thermal stability (189 degrees C) which is identified using thermal analysis. The thermal activation energy (77.286 kJ mol(-1)) is determined from TGA data. The good quality of the crystal is confirmed from the intense photoluminescence peak. The etching study revealed the elongated square pattern on the developed crystal surface.