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Experimental Evidence for Algebraic Double-Layer Forces.

ABSTRACT: According to conventional wisdom, electric double-layer forces normally decay exponentially with separation distance. Here, we present experimental evidence of algebraically decaying double-layer interactions. We show that algebraic interactions arise in both strongly overlapping as well as counterion-only regimes, albeit the evidence is less clear for the former regime. In both of these cases, the disjoining pressure profile assumes an inverse square distance dependence. At small separation distances, another algebraic regime is recovered. In this regime, the pressure decays as the inverse of separation distance.

SUBMITTER: Stojimirovic B

PROVIDER: S-EPMC6968886 | biostudies-literature | 2020 Jan

REPOSITORIES: biostudies-literature

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Experimental Evidence for Algebraic Double-Layer Forces.

Stojimirović Biljana B Vis Mark M Tuinier Remco R Philipse Albert P AP Trefalt Gregor G

Langmuir : the ACS journal of surfaces and colloids 20191231 1

According to conventional wisdom, electric double-layer forces normally decay exponentially with separation distance. Here, we present experimental evidence of algebraically decaying double-layer interactions. We show that algebraic interactions arise in both strongly overlapping as well as counterion-only regimes, albeit the evidence is less clear for the former regime. In both of these cases, the disjoining pressure profile assumes an inverse square distance dependence. At small separation dis ...[more]

PMID: 31834805

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