Cluster structure evolution in binary TMS-HO/DO mixtures: Insights into molecular interactions.

The hydrogen bonding network of tetramethylene sulfone (TMS)-water/heavy water binary solutions with different volume ratios was investigated using spontaneous and stimulated Raman spectra. The results indicate that, as the concentration of V increases, TMS does not engage in hydrogen bonding with water or heavy water. However, it influences the system by altering the molecular clustering of water and heavy water. In the mixed TMS-water binary solution, when the V is less than 60%, the addition of TMS leads to the transformation of the water molecules from a tetrahedral structure to dimers and trimers. In the TMS-heavy water binary solution, when the V is between 20% and 60%, the TMS leads to a change in the heavy water cluster structure by influencing the original force symmetry of the OD covalent bond, which causes the Raman peaks of OD symmetrical stretching vibration to shift to lower wavenumbers. When V is over 60%, the Raman peaks corresponding to the OH/D stretching vibration barely change due to the limited effect of excess TMS on the structure of water and heavy water clusters. When the V is over 25%, there is only one Raman peak in the stimulated Raman spectrum.