| Autor: |
Bühl M; Max-Planck-Institut für Kohlenforschung, Kaiser-Wilhelm-Platz 1, 45470 Mülheim/Ruhr, Germany. buehl@mpi-muelheim.mpg.de, Grigoleit S, Kabrede H, Mauschick FT |
| Jazyk: |
angličtina |
| Zdroj: |
Chemistry (Weinheim an der Bergstrasse, Germany) [Chemistry] 2005 Dec 23; Vol. 12 (2), pp. 477-88. |
| DOI: |
10.1002/chem.200500285 |
| Abstrakt: |
59Co chemical shifts were computed at the GIAO-B3LYP level for [Co(CN)6]3-, [Co(H2O)6]3+, [Co(NH3)6]3+, and [Co(CO)4]- in water. The aqueous solutions were modeled by Car-Parrinello molecular dynamics (CPMD) simulations, or by propagation on a hybrid quantum-mechanical/molecular-mechanical Born-Oppenheimer surface (QM/MM-BOMD). Mean absolute deviations from experiment obtained with these methods are on the order of 400 and 600 ppm, respectively, over a total delta(59Co) range of about 18,000 ppm. The effect of the solvent on delta(59Co) is mostly indirect, resulting primarily from substantial metal-ligand bond contractions on going from the gas phase to the bulk. The simulated solvent effects on geometries and delta(59Co) values are well reproduced by using a polarizable continuum model (PCM), based on optimization and perturbational evaluation of quantum-mechanical zero-point corrections. |
| Databáze: |
MEDLINE |
| Externí odkaz: |
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