O-17- and H-1-NMR studies of the water structure in binary aqueous mixtures of halogenated organic compounds

The chemical shifts of water (O-17- and H-1-NMR) and the spin-lattice relaxation time of water (O-17-NMR) were measured on binary aqueous mixtures of halogenated ethanols, propanols, acetamide and acetone to investigate the effect of their halogen groups on water structure. The solute molecules were 2-chloroethanol, 2-bromoethanol, 2-iodoethanol, 2,2-dichloroethanol, 3-chloropropan-1-ol, 2,3-dichloropropan-1-ol, chloroacetamide, and chloroacetone together with ethanol, propan-1-ol, acetamide and acetone. The results give clear evidence of the fact that the hydrogen bonds of the water molecules become weaker around the halogen group irrespective of the presence of an OH group in the molecules.