Εξειδίκευση τύπου :	Άρθρο σε επιστημονικό περιοδικό
Τίτλος:	Importance of Electron Correlation on the Geometry and Electronic Structure of [2Fe-2S] Systems: A Benchmark Study of the [Fe2S2(SCH3)4]2-,3-,4-, [Fe2S2(SCys)4]2-, [Fe2S2(S-p-tol)4]2-, and [Fe2S2(S-o-xyl)4]2- Complexes
Δημιουργός/Συγγραφέας:	[EL] Τζέλη, Δήμητρα[EN] Tzeli, Demeter Golub, Pavlo Brabec, Jiri Matoušek, Mikuláš Pernal, Katarzyna Veis, Libor Raugei, Simone Xantheas, Sotiris S
Ημερομηνία:	2024-11-19
Γλώσσα:	Αγγλικά
ISSN:	1549-9618 1549-9626
DOI:	10.1021/acs.jctc.4c00781
Άλλο:	39561296
Περίληψη:	Iron-sulfur clusters are crucial for biological electron transport and catalysis. Obtaining accurate geometries, energetics, manifolds of their excited electronic states, and reduction energies is important to understand their role in these processes. Using a [2Fe-2S] model complex with FeII and FeIII oxidation states, which leads to different charges, i.e., [Fe2S2(SMe)4]2-,3-,4-, we benchmarked a variety of computational methodologies ranging from density functional theory (DFT) to post-Hartree-Fock methods, including complete active space self-consistent field (CASSCF), multireference configuration interaction, the second-order N-electron valence state perturbation theory (NEVPT2), and the linearized integrand approximation of adiabatic connection (AC0) approaches. Additionally, we studied three experimentally well-characterized complexes, [Fe2S2(SCys)4]2-, [Fe2S2(S-o-tol)4]2-, and [Fe2S2(S-o-xyl)4]2-, via DFT methods. We conclude that the dynamic electron correlation is important for accurately predicting the geometry of these complexes. Broken symmetry (BS) DFT correctly predicts experimental geometries of low-spin multiplicity, while CASSCF does not. However, BS-DFT significantly overestimates the difference between the low- and high-spin electronic states for a given oxidation state. At the same time, CASSCF underestimates it but provides relative energies closer to the reference NEVPT2 results. Finally, AC0 provides energetics of NEVPT2 quality with the additional advantage of being able to use large CASSCF sizes. NEVPT2 gives the best estimates of the FeIII/FeIII → FeII/FeIII (4.27 eV) and FeII/FIII → FeII/FII (7.72 eV) reduction energies. The results provide insight into the electronic structure of these complexes and assist in the understanding of their physical properties.
Τίτλος πηγής δημοσίευσης:	Journal of chemical theory and computation
Θεματική Κατηγορία:	[EL] Χημεία[EN] Chemistry [EL] Φυσική και θεωρητική χημεία[EN] Physical and theoretical chemistry
Λέξεις-Κλειδιά:	chemical calculations quantum mechanics mathematical methods energy density functional theory
Κάτοχος πνευματικών δικαιωμάτων:	© 2024 American Chemical Society
Ηλεκτρονική διεύθυνση στον εκδότη (link):	https://doi.org/10.1021/acs.jctc.4c00781
Εμφανίζεται στις συλλογές:	Ινστιτούτο Θεωρητικής και Φυσικής Χημείας (ΙΘΦΧ) - Επιστημονικό έργο