| Full text | |
| Author(s): |
Total Authors: 3
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| Affiliation: | [1] Univ Marburg, Fachbereich Chem, D-35043 Marburg - Germany
Total Affiliations: 1
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| Document type: | Journal article |
| Source: | Journal of Physical Chemistry A; v. 113, n. 43, p. 11693-11698, OCT 29 2009. |
| Web of Science Citations: | 40 |
| Abstract | |
DFT calculations at the BP86/TZ2P level have been carried out for the compounds OCBBCO, N(2)BBN(2), and {[}OBBBBO](2-). The calculations predict very short distances,and large bond dissociation energies for the central B-B bonds. The nature of the bonding situation was investigated with an energy decomposition analysis. It shows that the central boron-boron bonds' are genuine triple bonds. The pi-bonding contributes between 38-40% to the total orbital interactions of the B B bonds. The compounds can be considered as donor-acceptor complexes L-BB-L between the central B(2) moiety in the third {[}(3)(1)Sigma(+)(g)] excited state and the ligands L = CO, N(2), BO(-). The pi-backdonation L-BB-L for L = CO, N(2) is very strong, which suggests that the latter bonds should also be considered as triple bonds. The pi-bonding in {[}OB <- BB -> BO](2-) is weaker, which makes the latter bonds borderline cases for triple bonds. The triple-bond character explains the very large bond dissociation energies for the LB-BL and L-BB-L bonds. (AU) | |