Synthesis, crystal structures, spectroscopic and nonlinear optical properties of chalcone derivatives: A combined experimental and theoretical study

A set of chalcone compounds were prepared by reacting p-bromoacetophenone with various substituted aromatic aldehyde in ethanol using sodium ethoxide as base. The synthesized molecules were well characterized using spectroscopic techniques like UV-Vis, fourier transform infrared (FT-IR) and nuclear magnetic resonance (H-1 & C-13) spectroscopy. The compounds were crystalized and their final structures were confirmed after diffracting these on single crystal X-ray diffractometer. The spectroscopic and molecular information were compared with simulated properties calculated via density functional theory (DFT). Geometries of all chalcone compounds have been optimized by density functional theory (DFT) at B3LYP level with 6-311 + G(d,p) basis set combination. Theoretical investigations about UV-Vis and FT-IR spectra of chalcone derivatives were reported using time dependent TD/DFT/B3LYP/6-311 + G(d,p) and B3LYP/6-311 + G(d,p) level respectively. The current study revealed that the theoretical findings complement the experimental results. Nonlinear optical properties of chalcone systems were calculated to gain insights the possibility of designing these compounds as NLO materials. The findings suggested that the first order hyperpolarizability of all the molecules except 1-(4-bromophenyl)-3-(1-methyl-1H-pyrrol-3-yl)prop-2-en-1-oneis also greater than the value of urea (beta = 0.372 x 10(-30) esu). These high values might be produced because of the dipole, molecular alignment and also from the non-covalent interactions. The domination of a particular component indicates a substantial delocalization of charges in that direction. (C) 2017 Elsevier B.V. All rights reserved.