Vibrational spectroscopy and density functional theory analysis of 3-O-caffeoylquinic acid

► Infrared and Raman spectra were recorded and compared with the theoretical results. ► The complete assignments are performed on the basis of the potential energy distribution. ► The theoretical calculations were made using B3LYP/6-311G(d,p) method. ► Stability of the molecule has been analyzed using natural bond orbital analysis. ► The HOMO and LUMO energies show that charge transfer occurs within the molecule.