Correction to “Confinement Induced Dilution: Electrostatic Screening Length Anomaly in Concentrated Electrolytes in Confined Space”

Screening of a surface charge by an electrolyte and the resulting interaction energy between charged objects is of fundamental importance in scenarios from bio-molecular interactions to energy storage. The conventional wisdom is that the interaction energy decays exponentially with object separation and the decay length is a decreasing function of ion concentration; the interaction is thus negligible in a concentrated electrolyte. Contrary to this conventional wisdom, we have shown by surface force measurements that the decay length is an increasing function of ion concentration and Bjerrum length for concentrated electrolytes. In this paper we report surface force measurements to test directly the scaling of the screening length with Bjerrum length. Furthermore, we identify a relationship between the concentration dependence of this screening length and empirical measurements of activity coefficient and differential capacitance. The dependence of the screening length on the ion concentration and the Bjerrum length can be explained by a simple scaling conjecture based on the physical intuition that solvent molecules, rather than ions, are charge carriers in a concentrated electrolyte.

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Scaling Analysis of the Screening Length in Concentrated Electrolytes

Physical Review Letters ◽

10.1103/physrevlett.119.026002 ◽

2017 ◽

Vol 119 (2) ◽

Cited By ~ 68

Author(s):

Alpha A. Lee ◽

Carla S. Perez-Martinez ◽

Alexander M. Smith ◽

Susan Perkin

Keyword(s):

Scaling Analysis ◽

Screening Length ◽

Concentrated Electrolytes

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Information and Dose in the Scanning Transmission Ion Microscope

Proceedings, annual meeting, Electron Microscopy Society of America ◽

10.1017/s1431927600001021 ◽

1980 ◽

Vol 38 ◽

pp. 232-233

Author(s):

Fox T. R. ◽

R. Levi-Setti

Keyword(s):

Information Retrieval ◽

Electron Microscope ◽

Elastic Scattering ◽

Energy Loss ◽

Cross Sections ◽

Previous Analysis ◽

Single Scattering ◽

Screening Length ◽

Relative Damage ◽

Scanning Transmission

At an earlier meeting [1], we discussed information retrieval in the scanning transmission ion microscope (STIM) compared with the electron microscope at the same energy. We treated elastic scattering contrast, using total elastic cross sections; relative damage was estimated from energy loss data. This treatment is valid for “thin” specimens, where the incident particles suffer only single scattering. Since proton cross sections exceed electron cross sections, a given specimen (e.g., 1 μg/cm2 of carbon at 25 keV) may be thin for electrons but “thick” for protons. Therefore, we now extend our previous analysis to include multiple scattering. Our proton results are based on the calculations of Sigmund and Winterbon [2], for 25 keV protons on carbon, using a Thomas-Fermi screened potential with a screening length of 0.0226 nm. The electron results are from Crewe and Groves [3] at 30 keV.

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