The disappearance of the stable slightly-bent isomer of germasilaallenes and the appearance of its cyclic isomer
| Autor: | Hong-Wei Xi, Sultana Bedoura, Kok Hwa Lim, Mahasin Alam Sk |
|---|---|
| Rok vydání: | 2020 |
| Předmět: |
010405 organic chemistry
Chemistry Bent molecular geometry 010402 general chemistry Ring (chemistry) 01 natural sciences 0104 chemical sciences Inorganic Chemistry Crystallography Delocalized electron Potential energy surface Materials Chemistry Density functional theory Physical and Theoretical Chemistry Electronic properties Natural bond orbital |
| Zdroj: | Polyhedron. 192:114821 |
| ISSN: | 0277-5387 |
| Popis: | Systematic density functional theory (DFT) calculations and natural bond orbital (NBO) analyses were carried out to understand the reason behind the disappearance of linear and slightly-bent isomer of germasilaallenes and the bond-stretch phenomenon of their cyclic isomer, unusual electronic properties of highly-bent isomers of germasilaallenes. Our results show that in contrast to trisilaallene and trigermaallene, 1,3-digermasilaallene and 1-germadisilaallene do not have stable cyclic isomers, due to increased ring strains. DFT calculations and NBO analyses indicate that the stability of highly-bent isomers of germasilaallenes arise from three parts: p(terminal) → p(central) donor–acceptor interaction, p(terminal)-p(terminal) partial overlapping and the aromatic delocalization along the ring. Different from mono- and di-germasilaallene, DFT and CCSD calculations indicate that there is no stable minimum along the first half, from 180° to 90.0°, of the potential energy surface of trigermasilaallene. For trigermasilaallene, for bending angle α > 120.0°, π-π* orbital delocalization effect dominates the stability and when α |
| Databáze: | OpenAIRE |
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