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201.
Positivity - There is an error in Proposition 3.10. In fact, the stated proof only shows 相似文献
202.
Marco Reichel Mara Egenhöfer Burkhard Krumm Konstantin Karaghiosoff 《无机化学与普通化学杂志》2020,646(6):328-331
Fluoromethylating agents are a highly studied and controversely discussed class of compounds. New fluoromethyl pseudohalides FCH2N3, FCH2SCN, and FCH2SeCN were prepared for the first time and their physical and spectroscopic properties investigated. Their synthesis is performed conveniently by fluoromethylation of the respective silver or potassium pseudohalogenides with fluoroiodomethane. 相似文献
203.
Dr. Marco Marazzi Dr. Hugo Gattuso Dr. Maria Fumanal Dr. Chantal Daniel Dr. Antonio Monari 《Chemistry (Weinheim an der Bergstrasse, Germany)》2019,25(10):2519-2526
A computational investigation of the triplet excited states of a rhenium complex electronically coupled with a tryptophan side chain and bound to an azurin protein is presented. In particular, by using high-level molecular modeling, evidence is provided for how the electronic properties of the excited-state manifolds strongly depend on coupling with the environment. Indeed, only upon explicitly taking into account the protein environment can two stable triplet states of metal-to-ligand charge transfer or charge-separated nature be recovered. In addition, it is also demonstrated how the rhenium complex plus tryptophan system in an aqueous environment experiences too much flexibility, which prevents the two chromophores from being electronically coupled. This occurrence disables the formation of a charge-separated state. The successful strategy requires a multiscale approach of combining molecular dynamics and quantum chemistry. In this context, the strategy used to parameterize the force fields for the electronic triplet states of the metal complex is also presented. 相似文献
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José Luis Castrejon-Flores Oscar Ernesto Guevara-Moreno Raúl Ricardo Díaz-Contreras Atilano Gutiérrez-Carrillo Marco Franco-Pérez 《Phosphorus, sulfur, and silicon and the related elements》2013,188(11):1062-1066
AbstractWe present a multicomponent reaction strategy to synthesize a (dihydro-1H-benzo[d]imidazole)phosphonate family of compounds, using benzimidazoles, diethyl chlorophosphate and aliphatic amines as starting reactants. Giving its simplicity, our procedure involves reaction times of only few hours and avoid the usage of any catalyst agent. All the newly synthesized compounds were characterized by Nuclear Magnetic Resonance spectroscopy (1H, 13C and 31P) and mass spectrometry by the DART method. 相似文献
209.
Emilio Ignesti Roberto Buffa Lorenzo Fini Emiliano Sali Marco V. Tognetti Stefano Cavalieri 《Optics Communications》2012,285(6):1185-1189
We present an experimental and theoretical investigation, performed on hot sodium atoms in a ladder scheme, showing the control of the absorption and of the propagation velocity of a probe light pulse with a spectral bandwidth as large as 1.8 GHz. The predictions of the theoretical model compare favorably with the experimental results. 相似文献