State-Dependent Electron Delocalization Dynamics at the Solute-Solvent Interface: Soft X-ray Absorption Spectroscopy and Ab Initio Calculations

TL;DR

This study combines soft X-ray absorption spectroscopy and ab initio calculations to reveal how electron delocalization at the solute-solvent interface affects non-radiative decay channels in transition metal solutions.

Contribution

It provides a detailed understanding of state-dependent electron delocalization mechanisms using advanced spectroscopy and computational methods, clarifying the origin of spectral dips.

Findings

Spectral dips are caused by state-dependent electron delocalization.

Comparison of Fe2+, Fe3+, and Co2+ systems confirms the delocalization mechanism.

Multi-reference ab initio calculations match experimental spectral features.

Abstract

Non-radiative decay channels in the L-edge fluorescence spectra from transition metal-aqueous solutions give rise to spectral dips in X-ray transmission spectra. Their origin is unraveled here using partial and inverse partial fluorescence yields on the micro-jet combined with multi-reference ab initio electronic structure calculations. Comparing Fe2+, Fe3+, and Co2+ systems we demonstrate unequivocally that spectral dips are due to a state-dependent electron delocalization within the manifold of d-orbitals.