Ionic structure in the aqueous electrolyte glass LiCl center dot 4D(2)O

The difference methods of neutron diffraction and isotopic substitution were applied to Li+ and Cl- in the aqueous lithium chloride glass LiCl . 4D(2)O at 120 K (the glass transition T-g = 150 K). Results for the ionic hydration show that structural changes are more evident for the Cl- coordination than for the Li+ coordination. At the level of the anion-anion structure there is an appreciable increase in the nearest-neighbour coordination number over that in the liquid which suggests a greater degree of correlation between the Cl- anion and the water molecules. A model of the ionic structure is proposed to explain the relative ease of classification of concentrated aqueous lithium chloride solutions.