Tadeusz Marek Krygowski
نویسنده
چکیده
منابع مشابه
Application of the LFER in Organic Electrochemistry: Jnterpretation of the Hammett Reaction Constant (e) for Processes of Reversible Electroreduction in Aprotic Solvents
The paper is an overview of the application of the concept of linear free energy relationships (LFER), most notably through the Hammett equation, to investigations of reversible organic electrochemical reactions in aprotic solvents. In sequence the following topics are covered: the effect of solvent properties on the equilibrium, ion pairing effects, the direct application of Hammett's equation...
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An efficient algorithm leading to the Fries canonical structure is presented for benzenoid hydrocarbons. This is a purely topological approach, which is based on adjacency matrices and the Hadamard procedure of matrix multiplication. The idea is presented for naphthalene, as an example. The Fries canonical-structures are also derived for anthracene, coronene, triphenylene, phenanthrene, benz[a]...
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Two intramolecular interactions, i.e., (1) hydrogen bond and (2) substituent effect, were analyzed and compared. For this purpose, the geometry of 4- and 5-X-substituted salicylaldehyde derivatives (X = NO(2), H or OH) was optimized by means of B3LYP/6-311 + G(d,p) and MP2/aug-cc-pVDZ methods. The results obtained allowed us to show that substituents (NO(2) or OH) in the para or meta position w...
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Fulvene is a non-aromatic molecule, but variation of the electron-donating/withdrawing power of substituents exo to the five-membered ring can drive the system between the extremes of aromatic and antiaromatic, as judged by prediction of fully developed diatropic and paratropic ring currents through ab initio calculations made at the ipsocentric 6-31G**/CTOCD-DZ CHF level.
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تاریخ انتشار 2007