Jump to main content
Jump to site search


Structural relaxation, viscosity, and network connectivity in a hydrogen bonding liquid

Author affiliations

Abstract

In liquids, the ability of neighboring molecules to rearrange and jostle past each other is directly related to viscosity, the property which describes the propensity to flow. The presence of hydrogen bonds (H-bonds) complicates the molecular scale picture of viscosity. H-Bonds are attractive, directional interactions between molecules which, in some cases, result in transient network structures. In this work, we use experimental and computational methods to demonstrate that the timescale of H-bond network reorganization is the dominant dynamical timescale associated with viscosity for the case of the model H-bonding liquid n-methylacetamide (NMA). This molecule is a peptide analog which forms a transient linear H-bond network. Individual H-bond lifetimes and dynamical fluctuations were observed on the timescale of 1.5 ps, while collective motions and the longest lived population of H-bond partner lifetimes were observed on the order of 20 ps, in agreement with the Maxwell relaxation time. This identifies a mechanism which may aid in understanding the emergence of various complex phenomena arising from transient molecular structures, with implications ranging from the internal dynamics of proteins, to the glass transition, to better understanding the origins of the unique properties of H-bonding liquids.

Graphical abstract: Structural relaxation, viscosity, and network connectivity in a hydrogen bonding liquid

Back to tab navigation

Supplementary files

Publication details

The article was received on 14 Jun 2017, accepted on 19 Jul 2017 and first published on 21 Jul 2017


Article type: Paper
DOI: 10.1039/C7CP04013J
Citation: Phys. Chem. Chem. Phys., 2017, Advance Article
  •   Request permissions

    Structural relaxation, viscosity, and network connectivity in a hydrogen bonding liquid

    S. Perticaroli, B. Mostofian, G. Ehlers, J. C. Neuefeind, S. O. Diallo, C. B. Stanley, L. Daemen, T. Egami, J. Katsaras, X. Cheng and J. D. Nickels, Phys. Chem. Chem. Phys., 2017, Advance Article , DOI: 10.1039/C7CP04013J

Search articles by author

Spotlight

Advertisements