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Published on: August 12, 2019
The unusual electronic structure of dinitrosyl iron complexes
1Lehrstuhl für Theoretische Chemie, Universität Bonn, Bonn D-53115, Germany. shengfa.ye@thch.uni-bonn.de
Journal of the American Chemical Society
|March 4, 2010
Summary
Dinitrosyl iron complexes (DNICs) electronic structures were elucidated using Kohn-Sham density functional theory. This reveals a unique bonding and ligand field splitting pattern crucial for iron-sulfur cluster chemistry.
Area of Science:
- Inorganic Chemistry
- Bioinorganic Chemistry
- Computational Chemistry
Background:
- Dinitrosyl iron complexes (DNICs) play a role in iron-sulfur cluster chemistry.
- The precise electronic structure of DNICs remains poorly understood, hindering mechanistic insights.
Purpose of the Study:
- To determine the experimentally validated electronic structures of {Fe(NO)2}(9) and its reduced form {Fe(NO)2}(10).
- To elucidate the bonding and ligand field characteristics of DNICs.
Main Methods:
- Kohn-Sham density functional theory calculations.
- Analysis of electronic structures to reproduce experimental parameters.
- Characterization of spin states and coupling in DNIC species.
Main Results:
- The electronic structure of {Fe(NO)2}(9) is a hybrid of ferric and ferrous states with antiferromagnetic coupling.
- {Fe(NO)2}(10) features a high-spin ferrous center coupled to triplet nitrosyl ligands.
- A covalent bonding interaction and a "one-above-four" ligand field splitting pattern were identified.
Conclusions:
- The determined electronic structures provide a detailed understanding of DNICs.
- The unusual ligand field splitting pattern offers mechanistic insights into iron-sulfur cluster transformations involving DNICs.
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