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Vincent De Waele Matthias Beutter Uli Schmidhammer Eberhard Riedle J rg Daub 《Chemical physics letters》2004,390(4-6):328-334
We report the first time resolved investigation of the ring opening dynamics of the 1,1-dicyano-2-(4-cyanophenyl)-1,8a-dihydroazulene (CN-DHA) towards its vinylheptafulvene (CN-VHF) isomer. The kinetics are measured by sub-30 fs transient absorption spectroscopy for numerous probe wavelengths from 485 to 690 nm. The ring opening takes place within 1.2 ps on the CN-DHA-VHF S1 potential energy surface. It is followed by the internal conversion from CN-VHF-S1 to CN-VHF-S0 in 13 ps. We observe coherent oscillations of low frequency modes (150, 190, 330 and 500 cm−1) that are closely associated with the skeleton motions driving the CN-DHA structural changes immediately after the 30 fs UV excitation. 相似文献
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Antoine Barthélemy Dr. Harald Scherer Dr. Michael Daub Alexis Bugnet Prof. Dr. Ingo Krossing 《Angewandte Chemie (International ed. in English)》2023,62(47):e202311648
The reaction of bisdicyclohexylphosphinoethane (dcpe) and the subvalent MI sources [MI(PhF)2][pf] (M=Ga+, In+; [pf]−=[Al(ORF)4]−; RF=C(CF3)3) yielded the salts [{M(dcpe)}2][pf]2, containing the first dicationic, trans-bent digallene and diindene structures reported so far. The non-classical MI⇆MI double bonds are surprisingly short and display a ditetrylene-like structure. The bonding situation was extensively analyzed by quantum chemical calculations, QTAIM (Quantum Theory of Atoms in Molecules) and EDA-NOCV (Energy Decomposition Analysis with the combination of Natural Orbitals for Chemical Valence) analyses and is compared to that in the isoelectronic and isostructural, but neutral digermenes and distannenes. The dissolved [{Ga(dcpe)}2]2+([pf]−)2 readily reacts with 1-hexene, cyclooctyne, diphenyldisulfide, diphenylphosphine and under mild conditions at room temperature. This reactivity is analyzed and rationalized. 相似文献
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Dr. Jörn Bruns Prof. Dr. Henning A. Höppe Dr. Michael Daub Prof. Dr. Harald Hillebrecht Prof. Dr. Hubert Huppertz 《Chemistry (Weinheim an der Bergstrasse, Germany)》2020,26(36):7966-7980
Borosulfates are oxoanionic compounds consisting of condensed sulfur- and boron-centered tetrahedra. Hitherto, they were mostly achieved from solvothermal syntheses in SO3-enriched sulfuric acid, or from reactions with the superacid H[B(HSO4)4]. The crystal structures are very similar to those of the corresponding class of silicates and their substitution variants, especially regarding the typical structural motif of corner-sharing tetrahedra. However, the borosulfates are supposed to be even more versatile, because (BO3) units might also be part of the anionic network. The following article deals with detailed reports on the different synthesis strategies, the crystal chemistry of borosulfates in comparison to silicates, and their hitherto identified properties. 相似文献
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