dc.contributor.author
Daldrop, Jan O.
dc.contributor.author
Kowalik, Bartosz G.
dc.contributor.author
Netz, Roland R.
dc.date.accessioned
2019-01-24T12:52:53Z
dc.date.available
2019-01-24T12:52:53Z
dc.identifier.uri
https://refubium.fu-berlin.de/handle/fub188/23783
dc.identifier.uri
http://dx.doi.org/10.17169/refubium-1569
dc.description.abstract
Stokes’s law for the friction of a sphere in water has been argued to work down to molecular scales, provided the effective hydrodynamic radius includes the hydration layer. In interpretations of experiments and in theoretical models, it is tacitly assumed that the solvent friction experienced by a solute does not depend on whether an external confinement potential acts on the solute. Using a novel method to extract the friction memory function from molecular dynamics simulations, we show that the solvent friction of a strongly harmonically confined methane molecule in water increases by 60% compared to its free-solution value, which is caused by an amplification of the slowest component of the memory function. The friction enhancement occurs for potential strengths typical of physical and chemical bonds and is accompanied by a significant slowing-down of the hydration water dynamics. Thus, the solvent friction acting on molecular solutes is not determined by solvent properties and solute-solvent interactions alone but results from the coupling between solute and solvent dynamics and thereby can be tuned by an external potential acting on the solute. This also explains why simulations of positionally constrained solutes do not reproduce free-solution diffusivities. Dynamic scaling arguments suggest similar effects also for macromolecular solutes provided the solution viscosity is sufficiently enhanced.
en
dc.format.extent
14 Seiten
dc.rights.uri
https://creativecommons.org/licenses/by/4.0/
dc.subject
Fluid-particle interactions
en
dc.subject
Langevin equation
en
dc.subject
Molecular dynamics
en
dc.subject
Stochastic differential equations
en
dc.subject.ddc
500 Naturwissenschaften und Mathematik::530 Physik::530 Physik
dc.title
External Potential Modifies Friction of Molecular Solutes in Water
dc.type
Wissenschaftlicher Artikel
dcterms.bibliographicCitation.articlenumber
041065
dcterms.bibliographicCitation.doi
10.1103/PhysRevX.7.041065
dcterms.bibliographicCitation.journaltitle
Physical Review X
dcterms.bibliographicCitation.number
4
dcterms.bibliographicCitation.volume
7
dcterms.bibliographicCitation.url
https://doi.org/10.1103/PhysRevX.7.041065
refubium.affiliation
Physik
refubium.resourceType.isindependentpub
no
dcterms.accessRights.openaire
open access
dcterms.isPartOf.issn
2160-3308