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Probing calcium solvation by XAS, MD and DFT calculations.

ABSTRACT: The solvation shell structures of Ca²⁺ in aqueous and organic solutions probed by calcium L-edge soft X-ray absorption spectroscopy (XAS) and DFT/MD simulations show the coordination number of Ca²⁺ to be negatively correlated with the electrolyte concentration and the steric hindrance of the solvent molecule. In this work, the calcium L-edge soft XAS demonstrates its sensitivity to the surrounding chemical environment. Additionally, the total electron yield (TEY) mode is surface sensitive because the electron penetration depth is limited to a few nanometers. Thus this study shows its implications for future battery studies, especially for probing the electrolyte/electrode interface for electrochemical reactions under in situ/operando conditions.

SUBMITTER: Yang F

PROVIDER: S-EPMC9055519 | biostudies-literature | 2020 Jul

REPOSITORIES: biostudies-literature

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Probing calcium solvation by XAS, MD and DFT calculations.

Yang Feipeng F Liu Yi-Sheng YS Feng Xuefei X Qian Kun K Kao Li Cheng LC Ha Yang Y Hahn Nathan T NT Seguin Trevor J TJ Tsige Mesfin M Yang Wanli W Zavadil Kevin R KR Persson Kristin A KA Guo Jinghua J

RSC advances 20200721 46

The solvation shell structures of Ca<sup>2+</sup> in aqueous and organic solutions probed by calcium L-edge soft X-ray absorption spectroscopy (XAS) and DFT/MD simulations show the coordination number of Ca<sup>2+</sup> to be negatively correlated with the electrolyte concentration and the steric hindrance of the solvent molecule. In this work, the calcium L-edge soft XAS demonstrates its sensitivity to the surrounding chemical environment. Additionally, the total electron yield (TEY) mode is su ...[more]

PMID: 35516916

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