November 2, 2017 – Using neutrons produced at Oak Ridge National Laboratory, scientists discovered the molecular mechanism responsible for the flow in a hydrogen-bonding liquid, which has similar characteristics to the molecular motions in organic molecules such as DNA and proteins. Their observation demonstrates Maxwell’s Law, which relates how fast molecules inside a liquid rearrange to flow with a syrupy or water-like viscosity. “Maxwell’s theory was confirmed long ago for many liquids, but hydrogen-bonding liquids were a complicated exception,” University of Cincinnati professor Jonathan Nickels said. “We unexpectedly discovered that flow in this liquid was connected to fluctuations in the hydrogen-bond network connectivity, rather than the dynamics of molecular collisions or the fluctuations of H-bonds themselves.” Understanding this mechanism will help scientists develop safe and more environmentally friendly solvents and advance protein and water research for biomedical applications. The team used ORNL’s Spallation Neutron Source, a DOE user facility. Nickels’ team, including coauthors Stefania Perticaroli and Barmak Mostofian, published their findings in the Journal of Physical Chemistry Chemical Physics.