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Accurately predicting the oxidative stability of battery electrolytes is crucial for improving our understanding of high-voltage behavior and rational design of next-generation systems employing novel chemistries. However, commonly applied strategies based on evaluation of orbital occupancies of isolated molecules within density functional theory techniques neglect many-body solvation and interfacial effects that govern the electro-thermodynamics in real systems. Here, we advance a computational methodology that integrates molecular dynamics sampling of local solvation environments with explicit vertical ionization potential (IP) calculations to account for such effects. Our approach allows for both statistical accounting of IP distributions as well as prediction of the oxidized species (e.g., solvent vs anion decomposition). Application of this method to a matrix of electrolytes based on common lithium salts and solvents yields more detailed conclusions that often disagree with those gained through conventional calculations. We also demonstrate that this methodology can capture variations in IP associated with increased salt concentrations as well as the speciation and stability next to electrified model interfaces. This work offers a comprehensive accounting of the microscopic factors and electronic structure considerations that stabilize molecules and their unique solvation environment in modern electrochemical systems. 

Understanding the role of ferroelectric polarization in modulating the electronic and structural properties of crystals is critical for advancing these materials for overcoming various technological and scientific challenges. However, due to difficulties in performing experimental methods with the required resolution, or in interpreting the results of methods therein, the nanoscale morphology and response of these surfaces to external electric fields has not been properly elaborated. In this work we investigate the effect of ferroelectric polarization and local distortions in a BaTiO 3 perovskite, using two widely used computational approaches which treat the many-body nature of X-ray excitations using different philosophies, namely the many-body, delta-self-consistent-field determinant (mb-ΔSCF) and the Bethe–Salpeter equation (BSE) approaches. We show that in agreement with our experiments, both approaches consistently predict higher excitations of the main peak in the O–K edge for the surface with upward polarization. However, the mb-ΔSCF approach mostly fails to capture the L 2,3 separations at the Ti–L edge, due to the absence of spin–orbit coupling in Kohn–Sham density functional theory (KS-DFT) at the generalized gradient approximation level. On the other hand, and most promising, we show that application of the GW/BSE approach successfully reproduces the experimental XAS, both the relative peak intensities as well as the L 2,3 separations at the Ti–L edges upon ferroelectric switching. Thus simulated XAS is shown to be a powerful method for capturing the nanoscale structure of complex materials, and we underscore the need for many-body perturbation approaches, with explicit consideration of core-hole and multiplet effects, for capturing the essential physics in these systems. 

This is a correction to the original manuscript. The original manuscript had missing text describing funding sources.