Growth and characterization of hydroxyethylammonium picrate single crystals for third-order nonlinear optical applications

A centrosymmetric crystal structure has been determined by single crystal X-ray diffraction analysis of Hydroxyethylammonium Picrate (HEAP) crystals. It is mentioned for the first time in the literature for its monoclinic structure crystallizing in centrosymmetrical space group P21/c which is basically a donor acceptor organic material grown by slow evaporation solution growth technique. We used Fourier Transform Infra Red and Raman spectroscopy to study the intermolecular interactions present in the 1:1 combination of picric acid and ethanolamine. Optical, mechanical and thermal stabilities of the title crystal were carried out to propose the material for useful applications. Z-scan is used to measure the effective third-order nonlinear optical susceptibility, which is found to be 3.24 × 10−3 esu. The negative sign of the nonlinear refractive index n2 = −9.2 × 10−5 cm2 W−1, indicates that this material exhibits self-defocusing optical nonlinearity. We also report the details of theoretical studies of the macroscopic nonlinear optical properties and molecular orbital calculations by quantum chemical calculations.