Molecular Structure, Computational Studies and Nonlinear Optical properties of a New Organic Chalcone Crystal

Abstract

A new conjugated chalcone compound (Z)-2-(1-(1-(2,4-dimethylphenyl)-3-oxo-3-phenylprop-1-en-2-yl)pyridin-2(1H)ylidene) malononitrile was prepared and structurally analyzed using single-crystal X-ray diffraction. This new compound's quadratic and cubic susceptibilities at 1064 nm were analyzed and evaluated using the second and third harmonic generation methods after deposition in PMMA polymer thin films. These films have been used for the induced second harmonic generation measurements achieved using the corona poling technique. Complementary information on electric dipole moment, static dipole polarizability, and initial hyperpolarizability of this compound were obtained from the density functional theory (DFT) calculation performed at the DFT/B3LYP/6-311G++ (d, p) and Gaussian 09 software. The findings demonstrate that when compared to previous chalcone NLO crystals that have been published, the synthesized crystals had greater crystal transparency, polarizability, and π-conjugation. In particular, the (Z)-2-(1-(1-(2,4-dimethylphenyl)-3-oxo-3-phenylprop-1-en-2-yl)pyridin-2(1H)ylidene) malononitrile crystal's SHG and THG susceptibility are 0. 243 [pmV−1] and 41.13 10−22 [m2V−2], respectively. The combined findings demonstrate that the NLO properties depend only on the steric hindrance and the chemical structure, that is, the system of π-conjugated electrons.