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Ab initio Study of Complexation Process between Poly（amido-amine） and Nano-Silicon Dioxide

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Chinese Journal of Chemical Physics 2013年第3期26卷 277-286,I0003页

作者：靳涛吕海亮山东科技大学材料科学与工程学院青岛266590 山东科技大学化学与环境工程学院青岛266590

To understand better the molecular-level details of ≡Si＋（SC） or ≡SiO- （SOA） ion group to -NH2 teminated poly（amido-amine） dendrimers in the gas phase, density functional theory is used to optimize the minimum energy and transition state structures with UB3LYP/6- 311G（d） and HF/6-31G levels. The tertiary amine nitrogen and the amide oxygen are found to be the most favorable binding sites. The activation energies of the different active sites and the reaction steps of SC and/or SOA ion group and the amide sites are also analyzed. The stable compounds are formed via the electrostatic interaction and the coordination effect. The orientation of the amide O and the rotation of the branches minimizes the energy of the whole system.

关键词： Polyamidoamine Activation energy Transition state density functionaltheory

Analytical Bond-order Potential for hcp-Y

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Chinese Journal of Chemical Physics 2013年第5期26卷 526-532,I0003页

作者： Kai-min Fan Li Yang Jing Tang Qing-qiang Sun Yun-ya Dai Shu-ming Peng Xiao-song Zhou Xiao--tao ZU School of Physical Electronics University of Electronic Science and Technology of China ChenEdu610054 China Department of Physics and Engineering Technology Sichuan University of Arts and Science Dazhou635000 China Department of Chemistry and Chemical Engineering Sichuan University of Arts and Science Dazhou635000 China School of Science Huaihai Institute of Technology LianyunEanE 222005 China Institute of Nuclear Physics and Chemistry China Academy of Engineering Physics Mianyang 621900China

The lattice parameters, elastic constants, cohesive energy, structural energy differences, as well as the properties of point defects and planar defects of hexagonal closepacked yttrium （hcpY） have been studied with ab initio density functional theory for constructing an ex tensive database. Based on an analytical bondorder poial scheme, empirical manybody interatomic potential for hcpY has been developed. The model is fitted to some properties of Y, e.g., the lattice parameters, elastic constants, bulk modulus, cohesive energy, vacancy formation energy, and the structural energy differences. The present potential has ability to reproduce defect properties including the selfinterstitial atoms formation energies, vacancy formation energy, divacancy binding energy, as well as the bulk properties and the thermal dynamic properties.

关键词： Hexagonal close-packed yttrium Bond-order potential density functionaltheory Molecular dynamics

High Pressure Phase Stability of Ti with Self-consistent ab initio Lattice Dynamics Approach

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Chinese Journal of Chemical Physics 2015年第2期28卷 168-172,I0001页

作者：曾召益胡翠娥刘勋张伟蔡灵仓重庆师范大学物理与电子工程学院重庆400047 中国工程物理研究院流体物理研究所冲击波与爆轰物理国防科技重点实验室绵阳621900 日本熊本大学脉冲功率科学研究院熊本860-8555

The traditional quasiharmonic approximation cannot predict the phase diagram of Ti accu- rately, due to the well-known soften phonon modes of the β-Ti. By means of self-consistent ab initio lattice dynamics （SCAILD） method, in which the effects of phonon-phonon in- teractions are considered, the phonon dispersion relations at finite temperature for Ti are calculated. From the phonon dispersions, we extrapolat the acoustic velocities and harmonic elastic constants. The dynamical stable regions and phase diagram of Ti are also predicted successfully. The results show that SCAILD method can be designed to work for strongly anharmonic systems where the QHA fails.

关键词： Transition metal Lattice dynmnics Phase transition density functionaltheory

Electronic and magnetic properties of Cd-doped zigzag AlN nanoribbons from first principles

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Rare Metals 2016年第10期35卷 771-778页

作者： Razieh Beiranvand Physics Department Faculty of Science and EngineeringAyatollah Alozma Boroujerdi University BoroujerdLorestan 167 Iran

The effect of Cd impurity on the electronic structure and magnetic properties of hydrogen-terminated AlN nanoribbons with zigzag edges （ZAINNRs） was in- vestigate using the band structure results obtained through the full potential linearized augmented plane wave （FP- LAPW） method within the density functional theory （DFT）. The exchange correlation potential was treated by the generalized gradient approximation within the Perdew scheme. The calculated results show that the H-terminated zigzag AlN nanoribbon is semiconducting and nonmag- netic material with a direct band gap of about 2.78 eV, while the Cd-doped H-terminated ZAlNNR structures show complete （100 %） spin polarization very close to the Fermi level, which will result in spin-anisotropic transport. The charge transport is totally dominated by Cd spin down electrons in the H-terminated ZAlNNR. These results suggest potential applications for the development of using the A1N nanoribbons in nanoelectronics and magnetoelec-tronic devices as a base.

关键词： Electronic properties Zigzag AlN nanoribbon Magnetic properties density functionaltheory Full potential linearized augmented plane wave

Adsorption and Decomposition of NH3 on Ni/Pt（111） and Ni/WC（001） Surfaces： A First-Principles Study

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Chinese Journal of Chemical Physics 2016年第6期29卷 710-716,I0002页

作者： Ai-ai Shen Yi-lin Cao Schoolof:ChemistryandChemicalEnEineerin~.HenanNormalUniversity.Xinxi~n~453007.China

density functional theory was used to study the NH3 behavior on Ni monolayer covered Pt（111） and WC（001）. The electronic structure of the surfaces, and the adsorption and decomposition of NH3 were calculated and compared. Ni atoms in the monolayer behave different from that in Ni（111）. More dz2 electrons of Ni in monolayer covered systems were shifted to other regions compared to Ni（111）, charge density depletion on this orbital is crucial to NH3 adsorption. NH3 binds more stable on Ni/Pt（lll） and Ni/WC（001） than on Ni（111）, the energy barriers of the first N-H bond scission were evidently lower on Ni/Pt（111） and Ni/WC（001） than on Ni（111）, these are significant to NH3 decomposition. N recombination is the rate-limiting step, high reaction barrier implies that N2 is produced only at high temperatures. Although WC has similar properties to Pt, differences of the electronic structure and catalytic activities are observed for Ni/Pt（111） and Ni/WC （001）, the energy barrier for the rate-determined step increases on Ni/WC（001） instead of decreasing on Ni/Pt（lll） when compared to Ni（111）. the N recombination barrier by modifying To design cheaper and better catalysts, reducing Ni/WC（001） is a critical question to be solved.

关键词： Ni monolayer Electronic structure NH3 decomposition density functionaltheory

Interaction Mechanism of Nano-silicon Dioxide Modified by Poly（amidoamine） Dendrimers

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Chinese Journal of Chemical Physics 2012年第5期25卷 592-604,I0004页

作者： Tao Jin Xiao-yu Li College of Material Science and Engineering Shandong University of Science and TechnologyQingdao 265590China College of Material Science and Engineering Beijing University of Chemical TechnologyBeifing100020China

To gain insight into the attachment of =Si^＋（SC） ion （regarded as guest） to the lowest generation, NH2-terminated poly（amidoamine）（PAMAM） dendrimers （regarded as host） in the liquid phase, density functional theory is used to investigate the structures and energetics of the host-guest complex. The effect of solvent on the structures and energetics is also investigated. Various initial configurations of the ion bound to PAMAM are tested, and two stable conformers are found, i.e, types A （=Si^＋ is bound to the amine site） and C （=Si^＋ is bound to the amide site）. Types A and C are the most stable due to the chemical bond formations of Si-N° （amine nitrogen atoms） and Si-O, respectively. The IR spectra for the lowest energy conformers are thoroughly analyzed and compared with the available experimental data.

关键词： Poly(amidoamine) Nano-silicon dioxide Configuration density functionaltheory

Adsorption of NO and NH_3 over CuO/γ-Al_2O_3 catalyst

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Journal of Central South University 2011年第6期18卷 1883-1890页

作者：赵清森孙路石刘勇苏胜向军胡松 Suzhou Nuclear Power Research Institute State Key Laboratory of Coal Combustion Huazhong University of Science and Technology

The selective catalytic reduction reaction belongs to the gas-solid multiphase reaction, and the adsorption of NH3 and NO on CuO/γ-Al2O3 catalysts plays an important role in the reaction. Performance of the CuO/γ-Al2O3 catalysts was explored in a fixed bed adsorption system. The catalysts maintain nearly 100% NO conversion efficiency at 350℃. Comprehensive tests were carried out to study the adsorption behavior of NH3 and NO over the catalysts. The desorption experiments prove that NH3 and NO are adsorbed on CuO/γ-Al2O3 catalysts. The adsorption behaviors of NH3 and NO were also studied with the in-situ diffusion reflectance infrared Fourier transform spectroscopy methods. The results show that NH3 could be strongly adsorbed on the catalysts, resulting in coordinated NH3 and NH4＋. NO adsorption leads to the formation of bridging bidentate nitrate, chelating bidentate nitrate, and chelating nitro. The interaction of NH3 and NO molecules with the Cu2＋ present on the CAl2O3 （100） surface was investigated by using a periodic density functional theory. The results show that the adsorption of all the molecules on the Cu2＋ site is energetically favorable, whereas NO bound is stronger than that of NH3 with the adsorption site, and key information about the structural and energetic properties was also addressed.

关键词： CuO/γ-Al2O3 NH3 NO adsorption diffusion reflectance infrared Fourier transform spectroscopy density functionaltheory

Electronic structure and infrared spectrum of a W_n C^(0,±) (n = 1-6) cluster

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Chinese Physics B 2011年第10期20卷 204-211页

作者：张秀荣康张李郭文录 School of Mathematics and Physics Jiangsu University of Science and Technology School of Materials Science and Engineering Jiangsu University of Science and Technology

WnC0＇± （n= 1-6） clusters are investigated by using the density functional theory （DFT） at the B3LYP/LANL2DZ level. We find that the neutral, anionic and cationic ground state structures are similar within the same size, and constituted by substituting a C atom for one W atom in the structures of Wn＋1 clusters. The natural bond orbital （NBO） charge analyses indicate that the direction of electron transfer is from the W atom to the 2p orbital of the C atom. In addition, the calculated infrared spectra of the WnC0＇± （n= 2-6） clusters manifest that the vibrational frequencies of neutral, anionic and cationic clusters are similar in a range of 80 cm-1-864 cm-1. The high frequency, strong peak modes are found to be an almost stretched deformation of the carbide atom. Finally, the polarizabilities of WnC0＇± （n= 1-6） clusters are also discussed.

关键词： WnC0'± (n= 1-6) clusters electronic structure infrared spectrum density functionaltheory

Molecular Structure, Vibrational Spectrum and Ionization Energy of m-Dimethoxybenzene

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Chinese Journal of Chemistry 2007年第9期25卷 1238-1241页

作者：黄健涵黄可龙刘素琴罗琼 College of Chemistry and Chemical Engineering Central South UniversityChangshaHunan410083China The State Key Laboratory of Molecular Reaction Dynamics Institute of ChemistryChineseAcademy of Sciences Beijing100080China

The optimized molecular geometries of the three rotamers of m-dimethoxybenzene in the ground So and electronically excited Sl states were predicted by ab initio and density functional theory （DFF） calculations. Their vibrational spectra in the St state were studied by one color resonant two photon ionization （1C-R2PI） method, and their ionization energies were measured by two color resonant two photon ionization （2C-R2PI） experiment. The optimized molecular geometries showed that the total energy of conformer a was the lowest in the So state. Most of the active vibrations assigned from the 1C-R2PI spectrum were found to be of the in-plane ring modes. The ionization energies （IE） of conformers a, b and c were determined to be 63521, 64487 and 63755 cm^-1, respectively.

关键词： resonant two photon ionization vibrational spectrum ionization energy ab initio density functionaltheory