Synthesis, crystal structure, structural and spectroscopic analysis of (2E)-1-(4-chlorophenyl)-3-(4-methoxyphenyl)prop-2-en-1-one

Chalcones are privileged structures in chemistry because they present a variety of possibilities for the construction of new molecules, which can be obtained from natural sources or by synthesis. In the solid-state, chalcones can crystalize into various space groups, and their molecular arrangements are directly associated with their chemical and physical properties. The aim of the present work was to investigate the structural, vibrational, electronic and non-linear optical (NLO) properties of a novel chalcone crystal (2E)-1-(4-chlorophenyl)-3-(4-methoxyphenyl)prop-2-en-1-one (C₁₆H₁₃ClO₃, hereafter named CLPMP). This chalcone was synthesized and characterized by single-crystal X-ray Diffraction (XRD), Fourier Transform Raman (FT-Raman), Attenuated Total Reflection Fourier Transform Infrared (ATR-FTIR), and Ultraviolet-visible (UV-Vis) spectroscopy. The thermal stability of CLPMP was also evaluated by thermogravimetric analysis (TGA) and differential thermogravimetric (DTG). Theoretical quantum chemistry calculations were performed to obtain information about their chemical and physical properties. Our crystallographic data show that at room temperature, CLPMP has a monoclinic structure with P2₁/c space group, and four molecules per unit cell, with the following cell lengths: a = 15.5924 (4) Å, b = 14.5537 (4) Å, c = 5.90980 (10) Å, and β = 90.046(2)°. A comparison between the experimental and theoretical Raman spectra allowed us to assign all normal modes of this crystal. Through the experimental and theoretical UV absorption spectra of chalcone CLPMP, it was possible to identify the electronic transitions of its first six singlet states. From the Hirshfeld surfaces analysis it was verified that short intermolecular contacts are responsible for stabilizing the packing of the CLPMP crystal. Our NLO study and thermal analysis showed that the chalcone CLPMP can be a good material for optical applications.