Synthesis and structural, molecular, optical and thermal characterization of a new curcumin derivative: 3, 5-bis((E)-3,4-dimethoxybenzylidene)-1-(4-ethylbenzoyl) piperidin-4-one for NLO applications

Using Claisen-Schmidt condensation reaction and Schotten-Boumann reaction methods, a new organic nonlinear optical material 3,5-bis((E)-3, 4-dimethoxybenzylidene)-1-(4-ethylbenzoyl) piperidin-4-one (EDMBP) was synthesized by slow evaporation method. The SCXRD study reveals that the compound crystallizes in orthorhombic crystal system with a space group of P 2₁ 2₁ 2₁with lattice parameters a = 8.8583(5) Å, b = 9.8293(5) Å, c = 32.2761(17) Å and V = 2810.3(3) ų. Structure elucidated of the compound was carried out with the help of SHELXS 97 and SHELXL 14 software. The intermolecular hydrogen bonds stabilize the crystal system. Hirshfeld surfaces and their corresponding 2D fingerprint plots were generated from which the intermolecular interactions and the intra molecular contacts contribution to the total Hirshfeld surface in the crystal structure were obtained. Energy frameworks is employed to determine the pair-wise intermolecular interactions and its effect in stability of the molecule. The compound was characterized by NMR, FT-IR, FT-RAMAN, UV and PL spectral analysis. From the UV-Vis spectral data, the band gap energy is determined which is 3.96 eV. TGA/DTA thermal analysis was performed at the temperature up to 1000 °C. The second harmonic generation (SHG) efficiency of EDMBP was determined using Nd: YAG laser as a source and the title compound can be used as lead material in optoelectronic devices design and applications.