English (United Kingdom)

https://curated-unify.zendy.io/wp-json/zendy-region/v1/featured_content/oa?rat=en

https://curated-unify.zendy.io/wp-json/zendy-region/v1/highlighted_journal/

Global: Zendy Plus annual

Presents the access of premium content as premium feature

Premium Content

Presents the keyphrase highlighting as premium feature

Keyphrase Highlighting

Presents the summarisation as premium feature

Summarisation

Insights

Presents the pdf analysis as premium feature

PDF Analysis

Presents the zaia usage as premium feature

ZAIA

Global: Zendy Plus monthly

Global: Zendy Tools annual

Global: Zendy Tools monthly

Global: Zendy Free Plan

In order to understand the nature and dynamics of interfacial water moleculeson the surface of complex systems, large scale molecular dynamics simulationsof an aqueous micelle of cesium perfluorooctanoate surfactant molecules havebeen carried out. The lifetime and the intermolecular vibrational frequenciesof the hydrogen bonds that the water molecules form with the polar headgroupsof the surfactants, are calculated. Our earlier classification of theinterfacial water molecules, based on structural and energetic considerations,into bound and free type is further validated by their dynamics. Lifetimecorrelation functions of the water-surfactant hydrogen bonds show the longlived nature of the bound water species. The water molecules that are singlyhydrogen bonded to the surfactants have longer lifetime than those that formtwo such hydrogen bonds. The free water molecules that do not form any suchhydrogen bonds behave similar to bulk water in their reorientational dynamics.A few water molecules that form two such hydrogen bonds are orientationallylocked in for durations of the order of few hundreds of picoseconds. Theintermolecular vibrational frequencies of these interfacial water moleculesshows a significant blue shift in the librational band apart from a similarshift in the near neighbor bending modes, relative to water molecules in bulk.These blue shifts suggest an increase in rigidity in the structure aroundinterfacial water molecules. This is in good agreement with recent incoherent,inelastic neutron scattering data on macromolecular solutions. The results ofthe present simulations should be relevant to the understanding of dynamics ofwater near any hydrophilic surface.Comment: 36 Pages including 7 Figures; Submitted to Phys. Rev.

physical review. e, statistical physics, plasmas, fluids, and related interdisciplinary topics

Dynamics of bound and free water in an aqueous micellar solution: Analysis of the lifetime and vibrational frequencies of hydrogen bonds at a complex interface