Cation coordination polyhedra lead to multiple lengthscale organization in aqueous electrolytes

Wei, Yihui; Nienhuis, Emily T.; Mergelsberg, Sebastian T.; Graham, Trent R.; Guo, Qing; Schenter, Gregory K.; Pearce, Carolyn I.; Clark, Aurora E.

doi:10.1039/d3cc02416d

DOE OSTI · 2217314

Cation coordination polyhedra lead to multiple lengthscale organization in aqueous electrolytes

Wei, Yihui·Nienhuis, Emily T.·Mergelsberg, Sebastian T.·Graham, Trent R.·Guo, Qing·Schenter, Gregory K.·Pearce, Carolyn I.·Clark, Aurora E.

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Abstract

Understanding multiple lengthscale correlations in the pair distribution functions (PDFs) of aq. electrolytes is a persistent challenge. Here, the coordination chemistry of polyoxoanions supports an ion-network of cation-coordination polyhedra in NaNO 3(aq) and NaNO 2(aq) that induce long-range solution structure. Further, oxygen correlations associated with Na + -coordination polyhedra have two characteristics lengthscales; 3.5–5.5 Å and 5.5–7.5 Å, the latter solely associated oligomers. The PDF contraction between 5.5–7.5 Å observed in many electrolytes is attributed to the distinct O···O correlation found in dimers and dimer subunits within oligomers.

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Wei, Yihui, Nienhuis, Emily T., Mergelsberg, Sebastian T., Graham, Trent R., Guo, Qing, Schenter, Gregory K., Pearce, Carolyn I., Clark, Aurora E.. 2023-07-28. Cation coordination polyhedra lead to multiple lengthscale organization in aqueous electrolytes. https://doi.org/10.1039/d3cc02416d

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