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Elso M. Cruz Xabier Lopez Martín Sarobe Fernando P. Cossío Jesus M. Ugalde 《Journal of computational chemistry》1997,18(1):9-19
A G2 search of the triplet [H4, Si, P]+ potential energy surface (PES) was carried out, along with a study of a number of mechanisms for the reaction of the P+ (3P) ion with silane. The most stable isomer, which corresponds to the species resulting from transferring three hydrogen atoms from the silicon to the phosphorus atom, lies 67.3 kcal/mol below the reactants' level. The P+(SINGLE BOND)SiH4 ion-molecule complex also has remarkable stability, 20.4 kcal/mol. Bond properties were calculated and are discussed for all the stable species found on the PES. Various exothermic reaction paths were also fully characterized. The abstractions of a hydrogen molecule and a hydrogen atom, yielding species with P(SINGLE BOND)Si bonds, have comparable kinetic hindrance, although release of molecular hydrogen was found to be more exothermic. Finally, hydrogen and/or charge transfer reactions between P+ (3P) and silane are also discussed. © 1997 by John Wiley & Sons, Inc. 相似文献
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Reply to the Comment on: “Quantum Confinement in Hydrogen Bond” by Carlos da Silva dos Santos,Elso Drigo Filho,and Regina Maria Ricotta,Int. J. Quantum Chem. 2015, 115, 765–770 下载免费PDF全文
Carlos da Silva dos Santos Elso D. Filho Regina M. Ricotta 《International journal of quantum chemistry》2015,115(20):1512-1513
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A new route to 2-substituted-2,3-dihydro-2-hydroxymethyl-1,4-benzodioxins 3 based on the reaction of α-(2-hydroxyphenoxy)alkylketones 1 with dimethylsulphoxonium methylide in dimethylsulphoxide is reported. Besides the desired compounds 3 , the isomeric 2H-3,4-dihydro-1,5-benzodioxepines 4 were also isolated, generally as minor products. The concurrent formation of 3 and 4 has been interpreted as occurring through the intermediate oxiranes 2 , which can undergo intramolecular nucleophilic attack at either of the carbon atoms of the epoxy ring. 相似文献
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Carlos da Silva dos Santos Elso Drigo Filho Regina Maria Ricotta 《International journal of quantum chemistry》2015,115(12):765-770
In this work, the quantum confinement effect is proposed as the cause of the displacement of the vibrational spectrum of molecular groups that involve hydrogen bonds. In this approach, the hydrogen bond imposes a space barrier to hydrogen and constrains its oscillatory motion. We studied the vibrational transitions through the Morse potential, for the NH and OH molecular groups inside macromolecules in situation of confinement (when hydrogen bonding is formed) and nonconfinement (when there is no hydrogen bonding). The energies were obtained through the variational method with the trial wave functions obtained from supersymmetric quantum mechanics formalism. The results indicate that it is possible to distinguish the emission peaks related to the existence of the hydrogen bonds. These analytical results were satisfactorily compared with experimental results obtained from infrared spectroscopy. © 2015 Wiley Periodicals, Inc. 相似文献
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Margarita Tlahuextl Antonio R. Tapia‐Benavides Angelina Flores‐Parra Rosalinda Contreras Hugo Tlahuext Elso M. Cruz 《Heteroatom Chemistry》2005,16(6):513-519
3,3′‐[2,2′‐Oxy‐bis‐(4S‐methyl, 5R‐phenyl‐1,3,2‐oxazaborolidine)]ethylene ( 4a ) and 3,3′‐[2, 2′‐oxy‐(4S‐methyl‐5R‐phenyl‐1,3,2‐oxazaborolidine)‐ (1,3,2‐benzoxazaborolidine)]ethylene ( 4b ) were synthesized by the reaction of N,N′‐bis‐[(1R,2S)‐norephedrine]oxalyl ( 3a ) or N,N′‐[((1R,2S)‐norephedrine, o‐hydroxyphenylamine]oxalyl ( 3b ) with BH3‐THF. The molecular structure of these compounds was established by NMR and infrared spectroscopy. The molecular geometry for 4 was studied by means of theoretical methods, resulting in structures that were in total agreement with those obtained by spectroscopy data and X‐ray diffraction. © 2005 Wiley Periodicals, Inc. Heteroatom Chem 16:513–519, 2005; Published online in Wiley InterScience ( www.interscience.wiley.com ). DOI 10.1002/hc.20151 相似文献
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1,2-Diphenols reacted with 2-alkyl-3-chloro-1,2-epoxypropane to give a mixture of 1,4-benzodioxane, V, and 1,5-benzodioxepine, VII, alcohols. From potassium permanganate oxidation of benzodioxane compounds V the corresponding (2-alkyl-1,4-benzodioxan-2-yl)carboxylic acids II were obtained. In a preliminary pharmacological evaluation benzodioxane acids II did not show any effect on plasma cholesterol, while producing a moderate lowering of triglycerides. 相似文献
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The effect of confinement on the electronic energy and polarizability of a hydrogen molecular ion 下载免费PDF全文
Josimar Fernando da Silva Fabrício Ramos Silva Elso Drigo Filho 《International journal of quantum chemistry》2016,116(7):497-503
The electronic energy and the polarizability of a confined hydrogen molecular ion in the ground state and the first excited state, for cavities of different volumes, are calculated using the variational method. In the treatment adopted an alternative molecular wave function is introduced with only one variational parameter and based on wave functions used for confined atoms. © 2016 Wiley Periodicals, Inc. 相似文献
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