TY - JOUR
T1 - Enhanced Molecular Diffusivity through Destructive Interference between Electrostatic and Osmotic Forces
AU - Samanta, Tuhin
AU - Sarhangi, Setare Mostajabi
AU - Matyushov, Dmitry V.
N1 - Funding Information:
This research was supported by the National Science Foundation (Grant CHE-1800243) and through XSEDE resources (Grant TG-MCB080071) as well as ASU’s Research Computing for computational resources.
Publisher Copyright:
© 2021 American Chemical Society
PY - 2021/7/22
Y1 - 2021/7/22
N2 - Molecular charge asymmetrically distributed in a diffusing tagged particle causes a nonzero electrostatic force balanced by an opposing van der Waals (vdW) force. Fluctuations of electrostatic and vdW forces are highly correlated, and they destructively interfere in the force variance. This phenomenology is caused by the formation of a structurally frozen hydration layer for a particle diffusing in water and is responsible for a substantial speedup of translational diffusion compared to traditional theories of dielectric friction. Diffusion of proteins is insensitive to charge mutations, while smaller particles with asymmetric charge distribution can show a strong dependence of translational and rotational diffusion on molecular charge. Dielectric calculations of the electrostatic force require low values of ≃5 for the effective dielectric constant of interfacial water to be consistent with simulations.
AB - Molecular charge asymmetrically distributed in a diffusing tagged particle causes a nonzero electrostatic force balanced by an opposing van der Waals (vdW) force. Fluctuations of electrostatic and vdW forces are highly correlated, and they destructively interfere in the force variance. This phenomenology is caused by the formation of a structurally frozen hydration layer for a particle diffusing in water and is responsible for a substantial speedup of translational diffusion compared to traditional theories of dielectric friction. Diffusion of proteins is insensitive to charge mutations, while smaller particles with asymmetric charge distribution can show a strong dependence of translational and rotational diffusion on molecular charge. Dielectric calculations of the electrostatic force require low values of ≃5 for the effective dielectric constant of interfacial water to be consistent with simulations.
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U2 - 10.1021/acs.jpclett.1c01875
DO - 10.1021/acs.jpclett.1c01875
M3 - Article
C2 - 34255530
AN - SCOPUS:85111198678
SN - 1948-7185
VL - 12
SP - 6648
EP - 6653
JO - Journal of Physical Chemistry Letters
JF - Journal of Physical Chemistry Letters
IS - 28
ER -