Falk, K.K.FalkSavio, D.D.SavioMoseler, M.M.Moseler2022-03-062022-03-062020https://publica.fraunhofer.de/handle/publica/26141610.1103/PhysRevLett.124.105501Viscosities i and diffusion coefficients Ds of linear and branched alkanes at pressure 0 smaller than P smaller than 0.7  GPa and temperature T=500-600  K are calculated from molecular dynamics simulations. Combining Stokes-Einstein, free volume, and random walk concepts results in an accurate viscosity model for the considered P and T. All model parameters (hydrodynamic radius, random walk step size, and step frequency) are extracted from equilibrium molecular dynamics via microscopic ensemble averages rendering i(P,T) a parameter-free predictor for lubrication simulations.enbrownian motioncomplex fluidsdiffusiondissipative dynamicsinterparticle interactionslubricationRandom Walksrheological propertiesrheologyself-diffusiontribology620530journal article