In: The Journal of Physical Chemistry A, 2006, vol. 110, no. 49, p. 13332 -13340
Exchange coupling across the cyanide bridge in a series of novel cyanometalate complexes with CuII-NC-MIII (M = Cr and low-spin Mn,Fe) fragments has been studied using the broken-symmetry DFT approach and an empirical model, which allows us to relate the exchange coupling constant with σ-, π-, and π*-type spin densities of the CN⁻ bridging ligand. Ferromagnetic...
|
In: Tetrahedron, 2006, vol. 62, no. 48, p. 11106-11111
A new 1,3-dithiol-2-ylidene substituted naphthopyranone 2 has been synthesized and characterized. UV–vis spectroscopic and cyclic voltammetry results, interpreted on the basis of density functional theory, show that 2 displays an intramolecular charge-transfer transition and acts like a donor–acceptor (D–A) system. Furthermore, a weak fluorescence originating from the excited...
|
In: Chemical Physics Letters, 2006, vol. 427, no. 4-6, p. 449-454
Using a DFT based Ligand Field treatment (LFDFT) of the electronic structure of Co(II) and Cu(II) porphyrins (CoP and CuP) we analyse the origin of their EPR spectra. From a comparison between theoretical result on Co model clusters (CoP and CoP–ZnP dimer) we conclude that the g-tensor values are very sensitive to the axial coordination which stabilizes a ²A₁ ground state in good...
|
In: Chimia, 2005, vol. 59, no. 7-8, p. 504-510
The research activity within our laboratory of computational chemistry at the University of Fribourg is presented. In this review, a brief outline of a recently proposed Ligand Field Density Functional Theory (LFDFT) model for single nuclear and its extension to dimer transition metal complexes is given. Applications of the model to dinuclear complexes are illustrated for the interpretation...
|
In: Comptes Rendus Chimie, 2005, vol. 8(9-10), p. 1421-1433
An overview of the theory and applications of a recently proposed ligand-field density functional theory (LFDFT) is given. We describe a procedure based on DFT allowing to deduce the parameters of this non-empirical LF approach consisting of the following steps: (i) an average of configuration (AOC) DFT calculation, with equal occupancies of the d-orbitals is carried out (ii) with...
|
In: Monatshefte für Chemie / Chemical Monthly, 2005, vol. 136, no. 6, p. 925-963
Metal–ligand bonding in transition metal halide molecules and complexes with different central ions, oxidations states, and coordination numbers: CrIII X₆³⁻, CrIVX₄, CrIIX₂ (X = F,Cl,Br,I), MIIICl₆³⁻(M = Mo,W), MIII (H₂O)₆³⁺(M = Cr,Co) and Re₂Cl₈²⁻ has...
|
In: Inorganic Chemistry, 2005, vol. 44(8), p. 2954-2963
Metal (4f)-ligand (Cl 3p) bonding in LnCl63- (Ln = Ce to Yb) complexes has been studied on the basis of 4f->4f and Cl,3p->4f charge-transfer spectra and on the analysis of these spectra within the valence bond configuration interaction model to show that mixing of Cl 3p into the Ln 4f ligand field orbitals does not exceed 1%. Contrary to this, Kohn-Sham formalism...
|
In: International Journal of Quantum Chemistry, 2005, vol. 102, p. 119-131
Spin-orbit coupling has been introduced into our newly developed ligand field density functional theory (LFDFT), using the zero-order regular approximation as implemented into the Amsterdam density functional (ADF) code. Application of the formalism to a series of NiX₄²⁻ (X=F⁻, Cl⁻, Br⁻, I⁻) compounds shows the increasing importance of intra-ligand spin-orbit coupling across the F,...
|
In: Chemical Physics Letters, 2004, vol. 397(4-6), p. 441-446
Ligand field splitting energies of lanthanides Ln³⁺ (Ln = from Ce to Yb) in octahedral environment are calculated using the Hohenberg–Kohn theorems based orbital-free embedding formalism. The lanthanide cation is described at orbital level whereas its environment is represented by means of an additional term in the Kohn–Sham-like one-electron equations expressed as an explicit functional...
|
In: Chemical Physics Letters, 2004, vol. 399(4-6), p. 433-439
The new DFT based ligand field (LF) model is proposed to calculate the g- and A-tensors of [Co(acacen)] that is known to be a difficult case. The results obtained are compared with the ZORA approach implemented in ADF as well as with the experimental values. The calculations are in good agreement with the experimental data and demonstrate the ability of the method to reproduce the large...
|
