Análise estrutural e vibracional da 2-hidróxi-chalcona sob condições extremas de pressão

Abstract

2’-Hydroxychalcone (1-(2-hydroxyphenyl)-3-phenylprop-2-en-1-one) is an organic compound with promising pharmacological potential, particularly due to its anti-inflammatory activity attributed to the hydroxyl group, which inhibits the overproduction of nitric oxide (NO) during infections. In this work, a single crystal of 2’-hydroxychalcone was synthesized and structurally characterized. A vibrational study under varying pressure conditions was then carried out using Raman spectroscopy. The analysis of vibrational modes revealed significant changes associated with torsions and deformations near the α,β-unsaturated bond, as well as shifts in the aromatic rings and carbonyl region. Spectral evolution showed the appearance, disappearance, merging, and splitting of vibrational modes, indicating a possible second-order phase transition starting around 0.8 GPa, with discontinuities observed between 2 and 6 GPa. Additional analysis using group theory, density functional theory (DFT), and potential energy distribution (PED) allowed accurate mode assignment. Hirshfeld surface analysis and fingerprint plots confirmed intermolecular interactions such as C–H· · ·O contacts and π −π stacking, which drive the planar packing of the crystal. These findings contribute to the understanding of the structural and vibrational behavior of chalcones under extreme conditions, with potential applications in material science and pharmacology.