Lecture notes electron correlation magnetism pdf

Calzado, Coen de Graaf, and Nathalie Guihéry. Jean Paul Malrieu, Rosa Caballol, Carmen J.Journal of the American Chemical Society 2015, 137 Electron Hopping through Double-Exchange Coupling in a Mixed-Valence Diiminobenzoquinone-Bridged Fe2 Complex. Solvent-Triggered Cis/Trans Isomerism in Cobalt Dioxolene Chemistry: Distinguishing Effects of Packing on Valence Tautomerism.

Jana, Antonio Bauzá, Antonio Frontera, and Corine Mathonière. The Journal of Physical Chemistry A 2017, 121

Influence of Radical Bridges on Electron Spin Coupling. Phase Transition Coupled with Monocrystal Destruction. Valence–Tautomeric Interconversion in a Bis(dioxolene)cobalt Complex with Iminopyridine Functionalized by a TEMPO Moiety. Journal of Chemical Theory and Computation 2022, 18 Exchange Spin Coupling in Optically Excited States. Rybakowski, Dominik Benner, Carmen Herrmann, Gabriel Bester. This article is cited by 26 publications. The long correlation length (22 Å) of the itinerant electron that mediates this coupling indicates that high-spin π-delocalized organic molecules could find applications as nanoscale spin-polarized electron injectors and molecular wires. Furthermore, the strong interaction between the itinerant dioxolene electron and localized NN electron spins impacts our ability to understand the exchange interaction between delocalized electrons and pinned magnetic impurities in technologically important dilute magnetic semiconductor materials. We show that ferromagnetic coupling promoted by organic mixed-valency provides keen insight into the ability of single molecules to communicate spin information over nanoscale distances. The ferromagnetic exchange in 1 and 2 results from a spin-dependent delocalization (double exchange type) process and the origin of this strong electron correlation has been understood in terms of a valence bond configuration interaction (VBCI) model. The valence delocalization within the dioxolene dyad of 2 results in ferromagnetic alignment of two localized NN radicals separated by over 22 Å. The temperature-dependent magnetic susceptibility data for 2 reveals that an excited state spin doublet ( S T = 1/ 2) is populated at higher temperatures, indicating that the phenylene spacer modulates the magnitude of the magnetic exchange. The ferromagnetic exchange interaction in 1 is so strong that only the high-spin quartet state ( S T = 3/ 2) is thermally populated at temperatures up to 300 K. Near-IR electronic absorption spectroscopy for 1 and 2 reveals a low-energy optical band that has been assigned as a Ψ u → Ψ g transition involving bonding and antibonding linear combinations of delocalized dioxolene (SQ/Cat) valence frontier molecular orbitals. We describe the electronic structure and the origin of ferromagnetic exchange coupling in two new metal complexes, NN-SQ-Co III(py) 2Cat-NN ( 1) and NN-Ph-SQ-Co III(py) 2Cat-Ph-NN ( 2) (NN = nitronylnitroxide radical, Ph = 1,4-phenylene, SQ = S = 1/ 2 semiquinone radical, Cat = S = 0 catecholate, and py = pyridine).

Lecture notes electron correlation magnetism pdf