Ligand‐Exchange Processes on Solvated Beryllium Cations. Part III |
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| Authors: | Ralph Puchta Rudi van Eldik |
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| Affiliation: | 1. Inorganic Chemistry, Department of Chemistry and Pharmacy, University of Erlangen‐Nürnberg, Egerlandstrasse 1, D‐91058 Erlangen;2. Computer Chemistry Center, Department of Chemistry and Pharmacy, University of Erlangen‐Nürnberg, N?gelsbachstrasse 25, D‐91052 Erlangen |
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| Abstract: | On the basis of DFT calculations (B3LYP/6‐311+G**), the possibility to include solvent effects is considered in the investigation of the H2O‐exchange mechanism on [Be(H2O)4]2+ within the widely used cluster approach. The smallest system in the gas phase, [Be(H2O)4(H2O)]2+, shows the highest activation barrier of +15.6 kcal/mol, whereas the explicit addition of five H‐bonded H2O molecules in [{Be(H2O)4(H2O)}(H2O)5]2+ reduces the barrier to +13.5 kcal/mol. Single‐point calculations applying CPCM (B3LYP(CPCM:H2O)/6‐311+G**//B3LYP/6‐311+G**) on [Be(H2O)4(H2O)]2+ lower the barrier to +9.6 kcal/mol. Optimization of the precursor and transition state of [Be(H2O)4(H2O)]2+ within an implicit model (B3LYP(CPCM:H2O)/6‐311+G** or B3LYP(PCM:H2O)/6‐311+G**) reduces the activation energy further to +8.3 kcal/mol but does not lead to any local minimum for the precursor and is, therefore, unfavorable. |
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| Keywords: | Ligand‐exchange processes Beryllium cations Quantum‐chemical investigations Water‐exchange mechanism |
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