Related Experiment Video
Updated: May 16, 2025
Analyzing Melts and Fluids from Ab Initio Molecular Dynamics Simulations with the UMD Package
Published on: September 17, 2021
Correlating Viscosity Trends and Ultrafast Structural Dynamics in TMSO-Water and SFL-Water Binary Mixtures
Jiman He1, Min Lin2, Yuting Gao1
1Key Laboratory of Applied Surface and Colloid Chemistry, Ministry of Education; Shaanxi Key Laboratory of New Concept Sensors and Molecular Materials; School of Chemistry and Chemical Engineering, Shaanxi Normal University, Xi'an, 710119, China.
Abstract:
The hydrogen bonding dynamics in tetramethylene sulfoxide (TMSO)-water and sulfolane (SFL)-water binary mixtures were investigated by using FTIR spectroscopy, ultrafast IR spectroscopy, and molecular dynamics (MD) simulations. Despite TMSO and SFL sharing a similar cyclic backbone, markedly different viscosity behaviors were observed. By employing SCN- as a local probe, its distinct reorientational dynamics was observed that directly correlates with the contrasting viscosity trends in the two systems. In TMSO-water solutions, strong solute-water hydrogen bonding dominates water-water interactions, leading to a viscosity maximum at intermediate concentrations. Conversely, the dynamics of water molecules in SFL-water solutions is decoupled from bulk viscosity trends due to the weaker solute-water interactions. MD simulations further elucidate how the interplay between solute-water and water-water hydrogen bonding governs the viscosity trends. This work advances our understanding of hydrogen bonding in complex aqueous environments and provides a systematic approach for connecting molecular-level interactions to macroscopic fluid properties.
Related Concept Videos
02:34Comparing Intermolecular Forces: Melting Point, Boiling Point, and Miscibility
Temporary attractive forces like dispersion are present in all molecules, whether they are polar or nonpolar. They...
01:19Viscosity of Fluid
02:28Intermolecular Forces in Solutions
When the strengths of the intermolecular forces of attraction between solute and solvent species in a solution are no different than those present in the separated components, the solution is formed with no accompanying energy change. Such a solution is called an ideal solution. A mixture of ideal gases (or gases such as helium and argon,...
02:56Intermolecular Forces and Physical Properties
01:34The Fluid Mosaic Model
02:57Surface Tension, Capillary Action, and Viscosity
The various IMFs between identical molecules of a substance are examples of cohesive forces. The molecules within a liquid are surrounded by other molecules and are attracted equally in all directions by the cohesive forces within the liquid. However, the molecules on the surface of a liquid are attracted only by about one-half as many molecules. Because of the unbalanced molecular attractions on the surface molecules, liquids contract to form a shape that minimizes the number...