Assessing long-range contributions to the charge asymmetry of ion adsorption at the air–water interface

Abstract

Cations and anions have different affinities for the air-water interface. The intrinsic orientation of surface molecules suggests such an asymmetry, but the bias is dominated by solvent response that is spatially local and significantly nonlinear.

Multivalent network modifier upregulates bioactivity of multispecies biofilm-resistant polyalkenoate cement

“…, the so-called multivalent ZM ( m ZM) ( Fig. 2 B-ⅱ) [ [30] , [31] , [32] ]. Here, the activity of ZM represents the proportional dipole moment to deconstruct the BO network.…”

Quadrupole-mediated dielectric response and the charge-asymmetric solvation of ions in water

“…We recently demonstrated that an analogous treatment of interfacial solvation performs reasonably well in describing ion-specific adsorption to the air-water surface. 15 In all these approaches, charge asymmetry was built in a posteriori, whereas it is an emergent feature of the model defined by Eq. 19.…”

“…The polarization response to charging a solute is also distinct for cations and anions, with more substantial consequences. 15,20,21,34,41 Fig. 2a highlights this asymmetric response, which manifests in V q as a nonlinear dependence on q. Amending DCT to account for this nonlinear response is much more challenging than introducing a background potential V 0 .…”

“…The physical origins of this neutral cavity potential 9,20,21 V 0 are surprisingly challenging to identify precisely; profound ambiguities plague any attempt just to separate contributions of solvent molecules near the solute and those of a distant interface. [13][14][15][35][36][37][38][39][40] Putting aside the lack of a clear physical interpretation, the effects of a nonzero neutral cavity potential are straightforward to include in the DCT framework. Adding an interaction between the solute and this innate potential,…”

“…Despite numerous studies over the past century, major gaps in our understanding of aqueous solvation still exist, particularly for small, charged solutes and for environments that are spatially heterogeneous. Highlighting these gaps, active research continues to develop and apply increasingly sophisticated methods of spectroscopy [1][2][3][4][5][6] and computer simulation [7][8][9][10][11][12][13][14][15] in order to clarify the solvation of ions in aqueous systems.…”