jp0c09363_si_001.pdf (1.54 MB)
Confined Water Molecules in Binary Mixtures of Water and 2,6-Lutidine Near Lower Solution Critical Temperature
journal contribution
posted on 2020-12-28, 20:07 authored by Alexander A. Korotkevich, Huib J. BakkerWe study the concentration and temperature dependence of the reorientation
dynamics of water molecules in binary mixtures of water and 2,6-lutidine
below the lower solution critical temperature (LSCT) with femtosecond
mid-infrared pump–probe spectroscopy. The measurements reveal
the presence of water molecules interacting with both the hydrophobic
groups of lutidine and forming
a hydrogen bond with the nitrogen atom of lutidine. Both types of
molecules show a strongly decreased rotational mobility in comparison
to bulk water. From the temperature dependence of the slow water fraction,
we conclude that the lutidine molecules form clusters that decrease
in size when the temperature is decreased further below the LSCT.