[Temperature effect on the hydrogen bonding behavior between DMSO and water in aqueous DMSO solutions studied by...

In the present paper, DMSO/H2O mixture with the ratio of volume 1:1 was measured in the cooling process by Raman spectroscopy, and the Raman assignments was made to the DMSO molecular and water molecular. The results showed that the behavior between intra-molecular hydrogen bonds and inter-molecular hydrogen bonds of DMSO and water leads to the change in the Raman spectra of the S==O stretching vibration of DMSO and the O--H stretching vibration of water. Further analysis showed that the hydrogen bond between DMSO and water was enhanced in the course of temperature decreasing process (27 to -30 degrees C), and the intramolecular hydrogen bonds between water and water replaced the intermolecular hydrogen bonds of DMSO and water in the course of temperature decreasing process (-30 to -60 degrees C). The research provides experimental basis for hydrogen bonding theory in aqueous solution.