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Chinese Journal of Structural Chemistry 2012年第5期31卷 625-634页

作者： Abolfazl Shiroudi Ehsan Zahedi Chemistry Department Shahrood BranchIslamic Azad UniversityShahroodIran

Ab initio molecular orbital calculations have been used to investigate the thermal decomposition kinetics of 2-chloroethylethyldichlorosilane at the B3LYP/6-311＋G^＊＊,B3PW91/6-311＋G^＊＊,and MPW1PW91/6-311＋G^＊＊ levels of *** these methods,the results（activation parameters） obtained using the B3LYP/6-311＋G＊＊ level are in good agreement with the available experimental *** calculated data imply that in the unimolecular β-elimination reactions of the studied compound in the gas phase,the polarization of C（1）-Cl（3） and C（1）-H（4） bonds in the sense of C（1）^δ＋-Cl（3）^δ-and C（1）^δ＋-H（4）^δ-,respectively,is a determining factor in the gas phase elimination reactions 1,2 and *** of bond order,natural bond orbital charges,bond indexes,synchro-nicity parameters,and IRC calculations suggest the elimination of 2-chloroethylethyldichlorosilane via reactions 1～3 can be described as concerted and slightly *** transition state structures of these reactions are a four-membered cyclic structure.

关键词： theoretical chemistry molecular modeling thermal decomposition DFT nbo analysis IRC 2-chloroethylethyldichlorosilane

Hydrogen evolution reaction between small-sized Zr_(n)(n=2–5)clusters and water based on density functional theory

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Chinese Physics B 2023年第6期32卷 429-434页

作者：唐雷雷史顺平宋永胡家宝刁凯蒋静段湛江陈德良 College of Mathematics and Physics Chengdu University of TechnologyChengdu 610059China School of Physics and Electronics Guizhou Education UniversityGuiyang 550018China

Density functional theory(DFT)is used to calculate the most stable structures of Zr_(n)(n=2-5)clusters as well as the adsorption energy values of Zr_(n)(n=2-5)clusters after adsorbing single water *** results reveal that there is a significant linear relationship between the adsorption energy values and the energy gaps of the Zr_(n)(n=2-5)***,the calculations of the reaction paths between Zr_(n)(n=2-5)and single water molecule show that water molecule can react with Zr_(n)(n=2-5)clusters to dissociate,producing hydrogen,and O atoms mix with the clusters to generate Zr_(n)O(n=2-5),all of which are exothermic *** to the released energy,the Zr4 cluster is the most efficient in Zr_(n)(n=2-5)clusters reacting with single water *** natural population analysis(NPA)and density of states(DOS)demonstrate the production of hydrogen and orbital properties in different energy ranges,respectively,jointly forecasting that Zr_(n)O(n=2-5)will probably continue to react with more water *** findings contribute to better understanding of Zr's chemical reactivity,which can conduce to the development of effective Zr-based catalysts and hydrogen-production methods.

关键词： density functional theory hydrogen evolution reaction nbo analysis reaction pathways

Density functional study of Al-doped Au clusters

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Chinese Physics B 2009年第7期18卷 2709-2718页

作者：赵丽霞冯晓娟曹廷廷梁晓罗有华 Department of Physics East China University of Science and Technology

The equilibrium geometries and electronic properties of AunAl, up to n=13, have been systematically investigated using the density functional theory. The results show that, for the AunAl clusters, two patterns are identified. Pattern one （n=2, 3, 8）, the lowest-energy geometries prefer two-dimensional structures. Pattern two （n=4-7, 9-13）, the lowest-energy geometries prefer three-dimensional structures. According to the analysis of the binding energy and the fragmentation energy, AunAl clusters with odd n are found to be more stable than those with even n. The same trend of alternation can be illuminated according to the computational results in the HOMO-LUMO gap, the ionization potential, and the electron affinities. The Al atom not only changes the structures of pure gold clusters, but also enhances their stabilities. nbo analysis indicates 6s orbital of Au atom hybridizes with 3p orbital of Al atom.

关键词： AunAl clusters equilibrium geometries electronic properties nbo analysis

Synthesis, Crystal Structure and Theoretical Calculations of N-Benzyl-1-(5-(3-chlorophenyl)-1,3,4-oxadiazol-2-yl)cyclopentanamine

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Chinese Journal of Structural Chemistry 2018年第5期37卷 679-692页

作者： ALI Ramazania FATEMEH Zeinali Nasrabadi YOUNES Hanifehpour SANG WOO Jooc MASOOME Sheikhi KATARZYNA Slepokura TADEUSZ Lis FARIDEH Gouranlou Department of Chemistry University of Zanjan PO Box 45195-313 Zanjan Iran Department of Chemistry Faculty of Valiasr Tehran Branch Technical and Vocational University Tehran Iran School of Mechanical Engineering Yeungnam University Gyeongsan 712- 749 Republic of Korea Young Researchers and Elite Club Gorgan Branch Islamic Azad University Gorgan Iran Faculty of Chemistry University of Wroclaw 14 Joliot-Curie St. 50-383 Wroclaw Poland Department of Biosctence and Biotechnology Malek Ashtar University of Technology Tehran Iran

N-benzyl-1-（5-（3-chlorophenyl）-1,3,4-oxadiazol-2-yl）cyclopentanamine was synthesized via one-pot reaction of appropriate benzylamine, cyclopentanone,（N-isocyanimino）triphenylphosphorane and m-chlorobenzoic acid. The quantum theoretical calculations for crystal structure were performed by density functional theory（DFT/B3LYP/6-311＋G＊）. From the optimized structure, geometric parameters were obtained and experimental measurements were compared with the calculated data. Frontier molecular orbitals（FMOs）, total density of states（DOS）, molecular electrostatic potential（MEP）, molecular properties, natural charges, NMR parameters and nbo analysis for the product were investigated by theoretical calculations.

关键词： N-isocyaniminotriphenylphosphorane cyclopentanone m-chlorobenzoic acid 1 3 4-oxadiazole aza-Wittig reaction DFT nbo analysis

Quantum Mechanical Calculations of High-T<sub>c</sub>Fe-Superconductors

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Journal of Quantum Information Science 2021年第2期11卷 84-98页

作者： Ronald Columbié-Leyva Ulises Miranda Alberto López-Vivas Jacques Soullard Ilya G. Kaplan Instituto de Investigación en Materiales National Autonomous University of Mexico Ciudad de México México Institute of Atomic Physics and Spectroscopy University of Latvia Riga Latvia Instituto de Física National Autonomous University of Mexico Ciudad de México México

In introduction we presented a short historical survey of the discovery of superconductivity (SC) up to the Fe-based materials that are not superconducting in a pure state. For this type of material, the transition to SC state occurs in presence of different dopants. Recently in the Fe-based materials at high pressures, the SC was obtained at room critical temperature. In this paper, we present the results of calculations of the isolated cluster representing infinitum crystal with Rh and Pd as dopants. All calculations are performed with the suite of programs Gaussian 16. The obtained results are compared with our previous results obtained for embedded cluster using Gaussian 09. In the case of embedded cluster our methodology of the Embedded Cluster Method at the MP2 electron correlation level was applied. In the nbo population analysis two main features are revealed: the independence of charge density transfer from the spin density transfer and, the presence of orbitals with electron density but without spin density. This is similar to the Anderson’s spinless holon and confirms our conclusions in previous publications that the possible mechanism for superconductivity can be the RVB mechanism proposed by Anderson for high Tc superconductivity in cuprates.

关键词： Superconductivity Fe-Based Superconductors Embedded Cluster Method MP2 Method nbo analysis