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Specific cation effects at aqueous solution-vapor interfaces: Surfactant-like behavior of Li⁺ revealed by experiments and simulations.

ABSTRACT: It is now well established by numerous experimental and computational studies that the adsorption propensities of inorganic anions conform to the Hofmeister series. The adsorption propensities of inorganic cations, such as the alkali metal cations, have received relatively little attention. Here we use a combination of liquid-jet X-ray photoelectron experiments and molecular dynamics simulations to investigate the behavior of K⁺ and Li⁺ ions near the interfaces of their aqueous solutions with halide ions. Both the experiments and the simulations show that Li⁺ adsorbs to the aqueous solution-vapor interface, while K⁺ does not. Thus, we provide experimental validation of the "surfactant-like" behavior of Li⁺ predicted by previous simulation studies. Furthermore, we use our simulations to trace the difference in the adsorption of K⁺ and Li⁺ ions to a difference in the resilience of their hydration shells.

SUBMITTER: Perrine KA

PROVIDER: S-EPMC5754762 | biostudies-literature | 2017 Dec

REPOSITORIES: biostudies-literature

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Specific cation effects at aqueous solution-vapor interfaces: Surfactant-like behavior of Li+ revealed by experiments and simulations.

Perrine Kathryn A KA Parry Krista M KM Stern Abraham C AC Van Spyk Marijke H C MHC Makowski Michael J MJ Freites J Alfredo JA Winter Bernd B Tobias Douglas J DJ Hemminger John C JC

Proceedings of the National Academy of Sciences of the United States of America 20171009 51

It is now well established by numerous experimental and computational studies that the adsorption propensities of inorganic anions conform to the Hofmeister series. The adsorption propensities of inorganic cations, such as the alkali metal cations, have received relatively little attention. Here we use a combination of liquid-jet X-ray photoelectron experiments and molecular dynamics simulations to investigate the behavior of K+ and Li+ ions near the interfaces of their aqu ...[more]

PMID: 29078311

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Specific cation effects at aqueous solution-vapor interfaces: Surfactant-like behavior of Li⁺ revealed by experiments and simulations.

Publications

Specific cation effects at aqueous solution-vapor interfaces: Surfactant-like behavior of Li<sup>+</sup> revealed by experiments and simulations.

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