Probing solute-solvent interactions of transition metal complexes using L-edge absorption spectroscopy
- In order to tailor solution-phase chemical reactions involving transition metal complexes, it is critical to understand how their valence electronic charge distributions are affected by the solution environment. Here, solute-solvent interactions of a solvatochromic mixed-ligand iron complex were investigated using X-ray absorption spectroscopy at the transition metal L-2,L-3-edge. Due to the selectivity of the corresponding core excitations to the iron 3d orbitals, the method grants direct access to the valence electronic structure around the iron center and its response to interactions with the solvent environment. A linear increase of the total L-2,L-3-edge absorption cross section as a function of the solvent Lewis acidity is revealed. The effect is caused by relative changes in different metal-ligand-bonding channels, which preserve local charge densities while increasing the density of unoccupied states around the iron center. These conclusions are corroborated by a combination of molecular dynamics and spectrum simulations basedIn order to tailor solution-phase chemical reactions involving transition metal complexes, it is critical to understand how their valence electronic charge distributions are affected by the solution environment. Here, solute-solvent interactions of a solvatochromic mixed-ligand iron complex were investigated using X-ray absorption spectroscopy at the transition metal L-2,L-3-edge. Due to the selectivity of the corresponding core excitations to the iron 3d orbitals, the method grants direct access to the valence electronic structure around the iron center and its response to interactions with the solvent environment. A linear increase of the total L-2,L-3-edge absorption cross section as a function of the solvent Lewis acidity is revealed. The effect is caused by relative changes in different metal-ligand-bonding channels, which preserve local charge densities while increasing the density of unoccupied states around the iron center. These conclusions are corroborated by a combination of molecular dynamics and spectrum simulations based on time-dependent density functional theory. The simulations reproduce the spectral trends observed in the X-ray but also optical absorption experiments. Our results underscore the importance of solute-solvent interactions when aiming for an accurate description of the valence electronic structure of solvated transition metal complexes and demonstrate how L-2,L-3-edge absorption spectroscopy can aid in understanding the impact of the solution environment on intramolecular covalency and the electronic charge distribution.…
Author details: | Raphael M. JayORCiDGND, Vinicius Vaz da CruzORCiD, Sebastian EckertORCiDGND, Mattis FondellORCiD, Rolf MitznerORCiDGND, Alexander FöhlischORCiDGND |
---|---|
DOI: | https://doi.org/10.1021/acs.jpcb.0c00638 |
ISSN: | 1520-6106 |
ISSN: | 1520-5207 |
Pubmed ID: | https://pubmed.ncbi.nlm.nih.gov/32532156 |
Title of parent work (English): | The journal of physical chemistry : B, Condensed matter, materials, surfaces, interfaces & biophysical chemistry |
Publisher: | American Chemical Society |
Place of publishing: | Washington |
Publication type: | Article |
Language: | English |
Date of first publication: | 2020/06/12 |
Publication year: | 2020 |
Release date: | 2023/05/04 |
Tag: | basis-sets; charge-transfer; density; dynamics; electron localization; iron; solvation; spin-crossover; tranfer excited-state; x-ray-absorption |
Volume: | 124 |
Issue: | 27 |
Number of pages: | 10 |
First page: | 5636 |
Last Page: | 5645 |
Funding institution: | ERC-ADG-2014 -Advanced Investigator Grant under the Horizon 2020 EU; Framework Program for Research and Innovation [669531 EDAX] |
Organizational units: | Mathematisch-Naturwissenschaftliche Fakultät / Institut für Physik und Astronomie |
DDC classification: | 5 Naturwissenschaften und Mathematik / 53 Physik / 530 Physik |
Peer review: | Referiert |
Publishing method: | Open Access / Hybrid Open-Access |
License (German): | CC-BY - Namensnennung 4.0 International |