Simulations of hydration lubrication between surfaces

• Applicant: Professor Dr. Roland Netz
• Subject Area: Statistical Physics, Nonlinear Dynamics, Complex Systems, Soft and Fluid Matter, Biological Physics
• Term: from 2015 to 2018
• Project identifier: Deutsche Forschungsgemeinschaft (DFG) - Project number 269080843

• Final Report Year: 2018

Final Report Abstract

Summarizing our results, we have determined how the friction between biological surfaces depends on normal load and interlayer spacing, and we propose a heuristic expression describing the crossover from hydrodynamic friction to hydration lubrication. Furthermore, we have studied how the surface chemistry, including surface charge and polarity, as well as the presence of ions affect the structure of the interfacial layer. Finally, we have developed an analytical continuum model capable of extracting the interfacial viscosity, which is an important parameter appearing in the heuristic theory of hydration lubrication, from standard electrokinetic experiments.

Publications

• Atomistic Simulations of Wetting Properties and Water Films on Hydrophilic Surfaces. J. Chem. Phys. 146:164705, 2017
  M. Kanduč and R. R. Netz
  (See online at https://doi.org/10.1063/1.4979847)
• Hydration Friction in Nanoconfinement: From Bulk via Interfacial to Dry Friction. Nano Lett. 17:5969–5976, 2017
  A. Schlaich, J. Kappler and R. R. Netz
  (See online at https://doi.org/10.1021/acs.nanolett.7b02000)
• Orientation-Induced Adsorption of Hydrated Protons at the Air-Water Interface. Angew. Chem. Int. Ed. 56:15846–15851, 2017
  S. I. Mamatkulov, C. Allolio, R. R. Netz and D. J. Bonthuis
  (See online at https://doi.org/10.1002/anie.201707391)
• Power-law Electrokinetic Behavior as a Direct Probe of Effective Surface Viscosity. Chem. Phys Lett. 670:11–15, 2017
  Y. Uematsu, R. R. Netz and D. J. Bonthuis
  (See online at https://doi.org/10.1016/j.cplett.2016.12.056)
• Analytical Interfacial Layer Model for the Capacitance and Electrokinetics of Charged Aqueous Interfaces. Langmuir 34:9097–9113, 2018
  Y. Uematsu, R. R. Netz and D. J. Bonthuis
  (See online at https://doi.org/10.1021/acs.langmuir.7b04171)
• Anomalous Electrokinetics at Hydrophobic Surfaces: Effects of Ion Specificity and Interfacial Water Structure. Electrochim. Act. 259:1011–1020, 2018
  Q. Cao and R. R. Netz