The rotational spectra of the fluorobenzene⋯water and p-difluorobenzene⋯water dimers: Structure and internal dynamics

► Microwave spectra of fluorobenzene⋯water and para-difluorobenzene⋯water. ► Hydrogen bonding between water and aromatic ring. ► Structure analysis using rotational and nuclear quadrupole coupling constants. ► Water internal rotation analysis using a flexible model.