Studies of crystal growth, structural, spectral and optical properties of solution grown 2-phenylethylaminium p-nitrophenolate monohydrate single crystals for efficient nonlinear optical applications

•New organic third-order NLO efficient 2PPNP crystal was successfully grown.•2PPNP crystal belongs to monoclinic crystal system with space group C2/c.•Cutoff wavelength of 2PPNP crystal was 348 nm and thermally stable upto 120°C.•Third-order NLO refractive index of 2PPNP was found to be n2=2.5321 × 10−11 cm2/w.•2PPNP crystal was tolerant upto 100 g mechanical indentation was observed. 2-phenylethylaminium p-nitrophenolate monohydrate (2PPNP) single crystals were grown by evaporation of solvent method. Defect free 2PPNP crystal was subjected to single X-ray diffraction analysis and revealed the unit cell parameters, packing style. The molecular geometrical parameters, molecular orbital, first order hyperpolarizability, MEP map, Mulliken atomic charges and thermodynamic properties of 2-phenylethylaminium p-nitrophenolate monohydrate crystal were theoretically investigated by DFT calculations. FTIR, FT-Raman and NMR studies encompasses its functional components precisely to confirm the compound as 2PPNP. Optical transparency of the as-grown crystals was studied by using UV-Vis spectrum and it shows the transparency in the entire visible region. Photo-excitation of 2PPNP was examined to understand its light emitting behavior. Thermal stability of the grown was examined by TG-DTA analysis to understand the withstanding temperature of 2PPNP and its various endothermic reactions. Microhardness property of 2PPNP was evaluated upto 100 g indentation load and results are analyzed. The Z-scan study was made for the polished 2 mm thick 2PPNP defect free single crystal to evaluate its third-order nonlinearity for knowing the usefulness to optoelectronic applications. [Display omitted]