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Title: Ionic mobility driven by correlated van der Waals and electrostatic forces
Classical theories of dielectric friction make two critical assumptions: (i) friction due to van der Waals (vdW) forces is described by hydrodynamic drag and is independent of the ionic charge and (ii) vdW and electrostatic forces are statistically independent. Both assumptions turn out to be incorrect when tested against simulations of anions and cations with varying charge magnitude dissolved in water. Both the vdW and electrostatic components of the force variance scale linearly with the ionic charge squared. The two components are strongly anticorrelated producing simple relations for the total force variance in terms of self-variances. The inverse diffusion constant scales linearly with the charge squared. Solvation asymmetry between cations and anions extends to linear transport coefficients.  more » « less
Award ID(s):
2154465
PAR ID:
10399490
Author(s) / Creator(s):
;
Date Published:
Journal Name:
The Journal of Chemical Physics
Volume:
156
Issue:
20
ISSN:
0021-9606
Page Range / eLocation ID:
204501
Format(s):
Medium: X
Sponsoring Org:
National Science Foundation
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