Hydrogen bonding in concentrated aqueous solutions of 1,2-dimethoxyethane:Formation of water clusters

The hydrogen bonding in concentrated aqueous solutions of 1,2-dimethoxyetha ne was studied by Raman spectroscopy of the O-H stretching band of water at various concentrations in the temperature range 218-315 K. The isotropic R aman spectra were analyzed by band decomposition, and two major components were identified in the spectra. They were assigned to the O-H stretching vi brations of water monomers and water molecules participating in clusters. r espectively. The following picture of the hydration structure in the soluti ons emerged. Water molecules in concentrated aqueous solutions of 1.2-dimet hoxyethane can exist in two stable configurations-either participating in w ater clusters enclosed in cavities of 1,2-dimethoxyethane molecules, or as monomers bridging ether oxygen atoms. The clustering of water is driven by the cooperative strengthening of the hydrogen bonds in the clusters. The cl usters and the cavities are mutually stabilized by the extensive hydrogen b onding, and the size of the clusters is almost independent of temperature.