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Université de Fribourg

Density functional theory study of the multimode Jahn-Teller problem in the fullerene anion

Ramanantoanina, Harry ; Gruden-Pavlović, Maja ; Zlatar, Matija ; Daul, Claude A.

In: International Journal of Quantum Chemistry, 2012, p. -

The fullerene anion, C₆₀⁻, within the Ih point group, is a spherical molecule subject to the T ⊗ h Jahn–Teller (JT) distortion. The descent in symmetry goes to the three epikernel subgroups, namely D5d, D3d, and D2h. The last one completely removes the electronic...

Université de Fribourg

Magnetic criteria of aromaticity in a benzene cation and anion: how does the Jahn–Teller effect influence the aromaticity?

Andjelković, Ljubica ; Perić, Marko ; Zlatar, Matija ; Grubišić, Sonja ; Gruden-Pavlović, Maja

In: Tetrahedron Letters, 2011, vol. 53, no. 7, p. 794-799

The aromatic/antiaromatic behavior of the Jahn–Teller (JT) active benzene cation and anion has been investigated using Density Functional Theory (DFT) calculations of Nuclear Independent Chemical Shifts (NICS) and magnetic susceptibility. NICS parameters have been scanned along the Intrinsic Distortion Path (IDP) for the benzene cation showing antiaromaticity which decreases with increasing...

Université de Fribourg

Treatment of the multimode Jahn–Teller problem in small aromatic radicals

Gruden-Pavlović, Maja ; Garcia-Fernandez, Pablo ; Andjelkovic, Ljubica ; Daul, Claude A. ; Zlatar, Matija

In: The Journal of Physical Chemistry A, 2012, vol. 115, no. 39, p. 10801–10813

The family of the Jahn–Teller (JT) active hydrocarbon rings, CnHn (n = 5–7), was analyzed by the means of multideterminantal density functional theory (DFT) approach. The multimode problem was addressed using the intrinsic distortion path (IDP) method, in which the JT distortion is expressed as a linear combination of all totally symmetric normal...

Université de Fribourg

Computational analysis of tris(1,2-ethanediamine) cobalt(III) complex ion: calculation of the ⁵⁹Co shielding tensor using LF-DFT

Senn, Florian ; Zlatar, Matija ; Gruden-Pavlovic, Maja ; Daul, Claude

In: Monatshefte für Chemie - Chemical Monthly : an International Journal of Chemistry, 2011, vol. 142, no. 6, p. 593-597

The ligand-field density functional theory (LF-DFT) approach is employed for calculations of the ⁵⁹Co nuclear magnetic resonance (NMR) shielding tensor of all four diastereoisomers (λλλ, λλδ, λδδ, and δδδ) of tris(1,2-ethanediamine) cobalt(III) complex ion, [Co(en)₃]³⁺. The obtained values split into two groups according to the point group of the diastereoisomers. The...

Université de Fribourg

A new method to describe the multimode Jahn-Teller effect using density functional theory

Zlatar, Matija ; Schläpfer, Carl-Wilhelm ; Daul, Claude A.

In: Springer Series in Chemical Physics, 2010, vol. 97, p. 131-165

A new method for the analysis of the adiabatic potential energy surfaces of Jahn–Teller (JT) activemolecules is presented. It is based on the analogy between the JT distortion and reaction coordinates. Within the harmonic approximation the JT distortion can be analysed as the linear combination of all totally symmetric normal modes in the low symmetry minimum energy conformation. Contribution...

Université de Fribourg

Intrinsic distortion path in the analysis of the Jahn–Teller effect

Zlatar, Matija ; Gruden-Pavlović, Maja ; Schläpfer, Carl-Wilhelm ; Daul, Claude A

In: Journal of Molecular Structure: THEOCHEM, 2010, vol. 954, p. 86-93

The multideterminental-DFT approach was performed in order to calculate the Jahn–Teller (JT) parameters for the JT active molecules. Within the harmonic approximation the JT distortion can be analysed as a linear combination of all totally symmetric normal modes in any of the low symmetry minimum energy conformation, which allows to calculate the Intrinsic Distortion Path (IDP), exactly from...

Université de Fribourg

Density functional theory for the study of the multimode Jahn-Teller effect

Zlatar, Matija ; Gruden-Pavlović, Maja ; Schläpfer, Carl-Wilhelm ; Daul, Claude A.

In: Chimia, 2010, vol. 64, no. 3, p. 161-164

The Jahn-Teller (JT) theorem states that in a molecule with a degenerate electronic state, a structural distortion must occur that lowers the symmetry, removes the degeneracy and lowers the energy. The multideterminental-DFT method performed to calculate the JT parameters for JT active molecules is described. Within the harmonic approximation the JT distortion can be analyzed as a linear...

Université de Fribourg

DFT Study of the Jahn-Teller Effect in Cu(II) Chelate Complexes

Gruden-Pavlović, Maja ; Zlatar, Matija ; Schläpfer, Carl-Wilhelm ; Daul, Claude A.

In: Journal of Molecular Structure: THEOCHEM, 2010, p. -

Density Functional Theory (DFT) in conjuction with the Intrinsic Distortion Path (IDP) is employed to study the Jahn-Teller (JT) effect in all four diastereoisomers of tris(ethylenediamine)copper(II) ([Cu(en)₃]²⁺) and tris(ethyleneglycol)copper(II) ([Cu(eg)₃]²⁺) complexes. As a consequence of the JT effect all the isomers tetragonally elongate to the C₂ configurations. Although there...

Université de Fribourg

Density functional theory study of the Jahn-Teller effect in cobaltocene

Zlatar, Matija ; Schläpfer, Carl-Wilhelm ; Fowe, Emmanuel Penka ; Daul, Claude A.

In: Pure and Applied Chemistry, 2009, vol. 81, no. 8, p. 1397-1411

A detailed discussion of the potential energy surface of bis(cyclopentadienyl)cobalt(II), cobaltocene, is given. Vibronic coupling coefficients are calculated using density functional theory (DFT). Results are in good agreement with experimental findings. On the basis of our calculation there is no second-order Jahn–Teller (JT) effect as predicted by group theory. The JT distortion can be...

Université de Fribourg

Molecular mechanics study of nickel(ii) octaethylporphyrin adsorbed on graphite (0001)

Gruden-Pavlović, Maja ; Grubišić, Sonja ; Zlatar, Matija ; Niketić, Svetozar R.

In: International Journal of Molecular Sciences, 2007, vol. 8, p. 810-829

The effects of adsorption on the graphite(0001) surface on the nonplanar distortions of nickel(II) octaethylporphyrin were studied by molecular mechanics (MM) approach. Using the Consistent Force Field (CFF) program with previously developed parameters for metalloporphyrins and supplemented to treat intermolecular interactions geometry optimizations were carried out for 43 conformations of 28...