Structural study, coordinated normal analysis and vibrational spectra of 4-hydroxy-3-(3-methyl-2-butenyl)acetophenone

► Vibrational spectra of 4-hydroxy-3-(3-methyl-2-butenyl)acetophenone were registered. ► Seven stable conformers have been theoretically determined. ► A complete assignment of the observed spectral features is proposed. ► The theoretical calculations allowed obtaining a set of scaled force constants. ► The nature of the phenyl ring was studied by NBO and AIM analysis.