Journal ArticleDOI
Valence bond description of antiferromagnetic coupling in transition metal dimers
TLDR
In this paper, a single configuration model containing nonorthogonal magnetic orbitals is developed to represent the important features of the antiferromagnetic state of a transition metal dimer.Abstract:
A single configuration model containing nonorthogonal magnetic orbitals is developed to represent the important features of the antiferromagnetic state of a transition metal dimer. A state of mixed spin symmetry and lowered space symmetry is constructed which has both conceptual and practical computational value. Either unrestricted Hartree–Fock theory or spin polarized density functional theory, e.g., Xα theory, can be used to generate the mixed spin state wave function. The most important consequence of the theory is that the Heisenberg exchange coupling constant J can be calculated simply from the energies of the mixed spin state and the highest pure spin multiplet.read more
Citations
More filters
Journal ArticleDOI
Reversible dioxygen binding to hemerythrin. 2. mechanism of the proton-coupled two-electron transfer to o2 at a single iron center
TL;DR: Brunold et al. as discussed by the authors explored the process of O2 release from binuclear non-heme iron protein hemerythrin (Hr) through density functional calculations that interpolate between these well-defined reference electronic structures.
Journal ArticleDOI
Strong Electronic Coupling between Dimolybdenum Units Linked by the N,N‘-Dimethyloxamidate Anion in a Molecule Having a Heteronaphthalene-like Structure
TL;DR: Calculations at the DFT level indicate that a strong transition in the near-IR region, shown by the singly oxidized and paramagnetic species, is best described as a HOMO-1 --> SOMO transition.
Journal ArticleDOI
Ferromagnetic Coupling in Hexanuclear Gadolinium Clusters
TL;DR: DFT calculations on model molecular systems indicate that the delocalized cluster bonding electrons are highly effective at mediating intracluster ferromagnetic exchange coupling between the Gd atom 4f7 moments and that intercluster coupling is expected to be antiferromagnetic.
Journal ArticleDOI
Spin polarization and annihilation for radicals and diradicals
TL;DR: In this article, the extent of spin polarization in unrestricted Hartree-Fock and density functional B3LYP calculations has been determined for a few monoradicals as well as the corresponding diradicals containing these monorads as functional groups.
Journal ArticleDOI
Antiferromagnetic Behavior Based on Quasi-Orthogonal MOs: Synthesis and Characterization of a Cu3 Oxidase Model
Boris Le Guennic,Sarah Petit,Guillaume Chastanet,Guillaume Pilet,Dominique Luneau,Nadia Ben Amor,Vincent Robert +6 more
TL;DR: It is shown that the Cu(3) oxidase model should be viewed as a "ménage à trois" spin-coupled pattern mediated by a central hydroxo group, lifting the doublet degeneracy by approximately 8 cm-1.
References
More filters
Journal ArticleDOI
New Approach to the Theory of Superexchange Interactions
TL;DR: In this article, the theory of indirect exchange in poor conductors is examined from a new viewpoint in which the $d$ (or $f$) shell electrons are placed in wave functions assumed to be exact solutions of the problem of a single $d-electron in the presence of the full diamagnetic lattice.
Journal ArticleDOI
Orbital interactions in metal dimer complexes
TL;DR: In this paper, the effect of geometrical distortions, electronegativity, and variation of substituents on the magnetic interaction in dimeric systems is examined in detail for singly bridged L,M-X-ML, (n = 3, 4, 5); Cu~C16~ and other doubly bridging species where the bridging ligands are halogens, OR, pyridine N-oxides, oxalate, squarate; and the acetate bridged dimers C u ~ (R C 0 0 ) 4.
Journal ArticleDOI
Quantum Theory of Many-Particle Systems. III. Extension of the Hartree-Fock Scheme to Include Degenerate Systems and Correlation Effects
TL;DR: In this paper, it was shown that if the total wave function is approximated by a projection of a single determinant, the description of the system may be reduced to the ordinary Hartree-Fock scheme treating this determinant.
Book ChapterDOI
Scattered-Wave Theory of the Chemical Bond
TL;DR: In the self-consistent field (SCF)-Xα scattered-wave model that is also a first-principle technique, there is no basis set problem because Schrodinger's equation for an Xα potential is numerically integrated as discussed by the authors.