Growth, structural, optical and thermal studies of semi-organic nonlinear optical potassium hydrogen oxalate single crystal

Abstract

Single crystals of semi-organic nonlinear optical material potassium hydrogen oxalate are grown from the aqueous solutions of potassium hydroxide and oxalic acid in 1:1 stoichiometric ratio by slow evaporation solution growth method at room temperature. The grown crystals are subjected to various characterization techniques to explore their structural explication, thermal, linear and nonlinear optical perspectives for optoelectronic device applications. The monoclinic structure with non-centrosymmetric space group P21/c of the titular compound has been confirmed by single-crystal X-ray diffraction. The crystal packing is ruled by extensive networks of hydrogen bonds revealed by the detailed study of the refinement of the crystal structure. Optical transparency of the crystal in the entire visible region has been confirmed by ultraviolet–visible-near infrared (UV–Vis-NIR) analysis. The robust thermal stability of the grown crystal is ensured by thermogravimetric–differential thermal analysis. The presence of expected functional groups in the grown crystal has been confirmed by Fourier transform infrared spectroscopic studies. Second-harmonic generation efficiency has been calculated by Kurtz powder method.