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First-principles calculations of structural and electronic properties of Tl_xGa_(1-x)As alloys
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作者 G. Bilgec akyüz A. Y. Tunali +1 位作者 S. E. Gulebaglan N. B. Yurdasan 《Chinese Physics B》 SCIE EI CAS CSCD 2016年第2期377-383,共7页
The zincblende ternary alloys Tl_xGa_(1-x) As(0 〈 x 〈 1) are studied by numerical analysis based on the plane wave pseudopotential method within the density functional theory and the local density approximation.... The zincblende ternary alloys Tl_xGa_(1-x) As(0 〈 x 〈 1) are studied by numerical analysis based on the plane wave pseudopotential method within the density functional theory and the local density approximation. To model the alloys,16-atom supercells with the 2 × 2 × 2 dimensions are used and the dependency of the lattice parameter, bulk modulus,electronic structure, energy band gap, and optical bowing on the concentration x are analyzed. The results indicate that the ternary Tl_xGa_(1-x) As alloys have an average band gap bowing parameter of 4.48 eV for semiconductor alloys and 2.412 eV for semimetals. It is found that the band gap bowing strongly depends on composition and alloying a small Tl content with GaAs produces important modifications in the band structures of the alloys. 展开更多
关键词 methods of electronic structure calculations electron density of states and band structure of crys-talline solids electronic structure of disordered solid
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Structural Phase Transitions of ZnTe under High Pressure Using Experiments and Calculations
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作者 程虎 李延春 +1 位作者 李工 李晓东 《Chinese Physics Letters》 SCIE CAS CSCD 2016年第9期95-99,共5页
The pressure-induced structural transitions of ZnTe are investigated at pressures up to 59.2 GPa in a diamond anvil cell by using synchrotron powder x-ray diffraction method. A phase transition from the initial zinc b... The pressure-induced structural transitions of ZnTe are investigated at pressures up to 59.2 GPa in a diamond anvil cell by using synchrotron powder x-ray diffraction method. A phase transition from the initial zinc blende (ZB, ZnTe-Ⅰ) structure to a cinnabar phase (ZnTe-Ⅱ) is observed at 9.6 GPa, followed by a high pressure orthorhombic phase (ZnTe-Ⅲ) with Cmcm symmetry at 12.1 GPa. The ZB, cinnabar (space group P3121), Cmcm, P31 and rock salt structures of ZnTe are investigated by using density functional theory calculations. Based on the experiments and calculations, the ZnTe-Ⅱ phase is determined to have a cinnabar structure rather than a P3 1 symmetry. 展开更多
关键词 ZNTE of structural Phase Transitions of ZnTe under High Pressure Using Experiments and calculations in
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Theoretical calculations of structural, electronic, and elastic properties of CdSe_(1-x)Te_x:A first principles study
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作者 M Shakil Muhammad Zafar +3 位作者 Shabbir Ahmed Muhammad Raza-ur-rehman Hashmi M A Choudhary T Iqbal 《Chinese Physics B》 SCIE EI CAS CSCD 2016年第7期324-330,共7页
The plane wave pseudo-potential method was used to investigate the structural, electronic, and elastic properties of Cd Se_(1-x)Te_x in the zinc blende phase. It is observed that the electronic properties are improv... The plane wave pseudo-potential method was used to investigate the structural, electronic, and elastic properties of Cd Se_(1-x)Te_x in the zinc blende phase. It is observed that the electronic properties are improved considerably by using LDA + U as compared to the LDA approach. The calculated lattice constants and bulk moduli are also comparable to the experimental results. The cohesive energies for pure Cd Se and Cd Te binary and their mixed alloys are calculated. The second-order elastic constants are also calculated by the Lagrangian theory of elasticity. The elastic properties show that the studied material has a ductile nature. 展开更多
关键词 first principles calculations density functional theory II–VI semiconductors structural electronic and elastic properties
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Application Strategy of Composite Steel Composite Beams in Bridge Design
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作者 Shengtang Wang 《Journal of World Architecture》 2024年第2期31-36,共6页
The combined prefabricated steel-hybrid stacked girder structure is very common in modern bridge design.An actual bridge engineering design project is taken as an example in this paper to analyze the application strat... The combined prefabricated steel-hybrid stacked girder structure is very common in modern bridge design.An actual bridge engineering design project is taken as an example in this paper to analyze the application strategy of this structure,encompassing overall design strategy,structural design strategy,and structural calculation strategy.The aim is to offer insights that can enhance the quality of bridge design. 展开更多
关键词 PREFABRICATION Steel-hybrid stacked girder Bridge design structural design and calculation
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Structural, magnetic properties, and electronic structure of hexagonal FeCoSn compound
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作者 李勇 代学芳 +7 位作者 刘国栋 魏志阳 刘恩克 韩小磊 杜志伟 郗学奎 王文洪 吴光恒 《Chinese Physics B》 SCIE EI CAS CSCD 2018年第2期476-481,共6页
The structural, magnetic properties, and electronic structures of hexagonal Fe Co Sn compounds with as-annealed bulk and ribbon states were investigated by x-ray powder diffraction(XRD), differential scanning calori... The structural, magnetic properties, and electronic structures of hexagonal Fe Co Sn compounds with as-annealed bulk and ribbon states were investigated by x-ray powder diffraction(XRD), differential scanning calorimetry(DSC), transmission electron microscope(TEM), scanning electron microscope(SEM), magnetic measurements, and first-principles calculations. Results indicate that both states of FeCoSn show an Ni_2In-type hexagonal structure with a small amount of FeCo-rich secondary phase. The Curie temperatures are located at 257 K and 229 K, respectively. The corresponding magnetizations are 2.57 μB/f.u. and 2.94 μB/f.u. at 5 K with a field of 50 kOe(1 Oe = 79.5775 A·m^(-1)). The orbital hybridizations between 3 d elements are analyzed from the distribution of density of states(DOS), showing that Fe atoms carry the main magnetic moments and determine the electronic structure around Fermi level. A peak of DOS at Fermi level accounts for the presence of the FeCo-rich secondary phase. The Ni_2In-type hexagonal FeCoSn compound can be used during the isostructural alloying for tuning phase transitions. 展开更多
关键词 FeCoSn hexagonal structure first-principles calculations
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QUANTUM CHEMICAL CALCULATIONS ON THE ELECTRONIC STRUCTURE AND SPECTRA OF[Mo_3O_4-nSn]^(4+)(n=O-4)CLUSTER CATIONS
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作者 Zhi Ru LI Qian Shu LI Ji Kang FANG Zhi Ren ZHENG Jun ZHENG Department of Chemistry,Jilin University,Changchun,130023 《Chinese Chemical Letters》 SCIE CAS CSCD 1992年第1期43-46,共4页
The electronic structure and spectra of [Mo3O4-nSn]^(4+)(n=0-4) cations were calculated by means of INDO/CI quantum chemistry method to account for the experimental data of their spectra in water solutions.
关键词 HOMO n=O-4)CLUSTER CATIONS Ho LUMO N QUANTUM CHEMICAL calculations ON THE ELECTRONIC STRUCTURE AND SPECTRA OF[Mo3O4-nSn MO
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Electronic Structure and Optical Properties in Uranium Dioxide:the First Principle Calculations
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作者 隋鹏飞 戴振宏 +1 位作者 张晓玲 赵银昌 《Chinese Physics Letters》 SCIE CAS CSCD 2015年第7期129-133,共5页
We report a study of the electronic structure and optical properties of uranium dioxide (U02) based on the ab-initio density-functional theory and using the generalized gradient approximation. To correctly describe ... We report a study of the electronic structure and optical properties of uranium dioxide (U02) based on the ab-initio density-functional theory and using the generalized gradient approximation. To correctly describe the strong correlation between 5 f electrons of a uranium atom, we employ the on-site Hubbard U correction term and optimize the correlation parameter of the bulk uranium dioxide. Then we give the structural and electronic properties of the ground state of uranium dioxide. Based on the accurate electronic structure, we calculate the complex dielectric function of UO2 and the related optieM properties, such as reflectivity, refractive index, extinction index, energy loss spectra, and absorption coefficient. 展开更多
关键词 LDA GGA Electronic Structure and Optical Properties in Uranium Dioxide:the First Principle calculations
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Synthesis,Crystal Structure and Band Structure of Sm_3In_5 被引量:5
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作者 岳呈阳 雷晓武 《Chinese Journal of Structural Chemistry》 SCIE CAS CSCD 2011年第3期384-389,共6页
A new intermetallic compound, Sm3In5, has been synthesized by solid-state reaction of the corresponding pure elements in a welded niobium tube at high temperature. Its crystal structure was established by single-cryst... A new intermetallic compound, Sm3In5, has been synthesized by solid-state reaction of the corresponding pure elements in a welded niobium tube at high temperature. Its crystal structure was established by single-crystal X-ray diffraction. Sm3In5 crystallizes in orthorhombic, space group Cmcm with a = 10.0137(8), b = 8.1211(7), c = 10.3858(8) A, V = 844.60(1) A^3, Z = 4, Mr = 1025.15, Dc = 8.062 g/cm^3, μ = 33.791 mm^-1, F(000) = 1724, the final R = 0.0346 and wR = 0.0775 for 533 observed reflections with I 〉 2σ(I). The structure of Sm3In5 belongs to the modified Pu3Pd5 type. It is isostructural with La3In5 and β-Y3In5, containing one-dimensional (1D) [In5] cluster chains along the c-axis, which are weakly interconnected via In-In bonds (3.345A) to form a three-dimensional (3D) structure. The samarium cations are located at the voids between the 1D [In5] cluster chains. Band structure calculations based on Density Function Theory (DFT) method indicate that Sm3In5 is metallic. 展开更多
关键词 INTERMETALLIC INDIDES crystal structure band structure calculation
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Synthesis,Crystal Structure,DFT Studies and Biological Activity of a Novel Schiff Base Containing Triazolo[4,3-a]pyridine Moiety 被引量:5
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作者 沈钟华 石延霞 +6 位作者 杨明艳 孙召慧 翁建全 谭成侠 刘幸海 李宝聚 赵卫光 《Chinese Journal of Structural Chemistry》 SCIE CAS CSCD 2016年第3期457-464,共8页
The novel Schiff base(E)-8-chloro-NA-(4-(dimethylamino)benzylidene)-[1,2,4]triazolo[4,3-a]pyridine-3-carbohydrazide was synthesized and characterized by ^1H NMR,MS,elemental analysis and X-ray diffraction.The co... The novel Schiff base(E)-8-chloro-NA-(4-(dimethylamino)benzylidene)-[1,2,4]triazolo[4,3-a]pyridine-3-carbohydrazide was synthesized and characterized by ^1H NMR,MS,elemental analysis and X-ray diffraction.The compound crystallizes in the monoclinic space group P2_1/c with a = 7.091(2),b = 10.750(3),c = 21.380(6) A,β = 96.299(6)°,V = 1619.7(8) A^3,Z = 4 and R = 0.0351.Theoretical calculation of the title compound was carried out with the B3LYP/6-31 G basis set.The frontier orbital energy and atomic net charges were discussed.It is found that the experimental data show good agreement with the calculated values.And the compound exhibits good antifungal activity against Stemphylium lycopersici(Enjoji) Yamamoto. 展开更多
关键词 1 2 4-triazolo[4 3-a]pyridine hydrazine synthesis crystal structure theoretical calculation antifungal activity
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Synthesis,Crystal Structure,DFT Studies and Antifungal Activity of 5-(4-Cyclopropyl-5-((3-fluorobenzyl)sulfonyl)-4H-1,2,4-triazol-3-yl)-4-methyl-1,2,3-thiadiazole 被引量:3
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作者 翟志文 石延霞 +6 位作者 杨明艳 孙召慧 翁建全 谭成侠 刘幸海 李宝聚 张永刚 《Chinese Journal of Structural Chemistry》 SCIE CAS CSCD 2016年第1期25-33,共9页
5-(4-Cyclopropyl-5-((3-fluorobenzyl)sulfonyl)-4H-1,2,4-triazol-3-yl)-4-methyl-1,2,3-thiadiazole was synthesized and recrystallized from Et OH. The compound was characterized by ^1H NMR,MS,elemental analysis and ... 5-(4-Cyclopropyl-5-((3-fluorobenzyl)sulfonyl)-4H-1,2,4-triazol-3-yl)-4-methyl-1,2,3-thiadiazole was synthesized and recrystallized from Et OH. The compound was characterized by ^1H NMR,MS,elemental analysis and X-ray diffraction. The structure-active relationship and the antifungal activity based on density functional theory calculation(DFT) and antifungal activities were investigated. The compound crystallizes in the monoclinic space group P121/n1 with a = 8.929(3),b=12.715(4),c=15.161(5) A°,β = 106.142(3)o,V = 1653.3(9) A°3,Z = 4 and R = 0.0393 for 3930 observed reflections with I 〉 2σ(I). Theoretical calculation of the title compound was carried out with B3LYP/6-31G(d,p). The full geometry optimization was carried out using the 6-31G(d,p) basis set.The frontier orbital energy and atomic net charges were discussed. The observed results of the compound have been compared with theoretical results and the experimental data show good agreement with the calculated values. The compound exhibits good antifungal activity. 展开更多
关键词 1 2 3-thiadiazole 1 2 4-triazole synthesis crystal structure theoretical calculation antifungal activity
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Synthesis and Crystal and Band Structures of YbCu_6In_6 with 3D Framework 被引量:2
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作者 雷晓武 岳呈阳 《Chinese Journal of Structural Chemistry》 SCIE CAS CSCD 2012年第3期389-395,共7页
A new intermetallic compound,YbCu6In6,has been synthesized by solid-state reaction of the corresponding pure elements in a welded tantalum tube at high temperature.Its crystal structure was established by single-cryst... A new intermetallic compound,YbCu6In6,has been synthesized by solid-state reaction of the corresponding pure elements in a welded tantalum tube at high temperature.Its crystal structure was established by single-crystal X-ray diffraction.YbCu6In6 crystallizes in tetragonal space group I4/mmm with a = 9.2283(5),c = 5.4015(4),V = 460.00(5) 3,Z = 2,Mr = 1243.20,Dc = 8.976 g/cm3,μ = 38.243 mm-1,F(000) = 1076,and the final R = 0.0258 and wR = 0.0602 for 173 observed reflections with I 〉 2σ(I).The structure of YbCu6In6 belongs to the ThMn12 type.It is isostructural with RECu6In6(RE = Y,Ce,Pr,Nd,Gd,Tb,Dy),containing one-dimensional(1D) [Cu10In6] cluster chain along the c axis,which is interconnected via sharing the Cu(1) atoms to form a three-dimensional(3D) [Cu6In6] framework with Yb atoms encapsulated in the 1D tunnels along the c axis.Band structure calculations based on Density Functional Theory(DFT) method indicate that YbCu6In6 is metallic. 展开更多
关键词 INTERMETALLIC INDIDES crystal structure band structure calculation
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Synthesis,Crystal Structure and Band Structure of Tb_3Co_4Sn_(13) 被引量:1
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作者 雷晓武 岳呈阳 《Chinese Journal of Structural Chemistry》 SCIE CAS CSCD 2011年第6期805-810,共6页
A new intermetallic compound,Tb3Co4Sn13,has been synthesized by solid-state reaction of the corresponding pure elements in a welded tantalum tube at high temperature.Its crystal structure was established by single-cry... A new intermetallic compound,Tb3Co4Sn13,has been synthesized by solid-state reaction of the corresponding pure elements in a welded tantalum tube at high temperature.Its crystal structure was established by single-crystal X-ray diffraction.Tb3Co4Sn13 crystallizes in cubic,space group Pm3n(No.223) with a = 9.5072(2) ,V = 859.33(3) 3,Z = 2,Mr = 2255.45,Dc = 8.717 g/cm3,μ = 34.369 mm-1,F(000) = 1906,and the final R = 0.0140 and wR = 0.0312 for 199 observed reflections with I〉 2σ(I).The structure of Tb3Co4Sn13 belongs to the Yb3Rh4Sn13 type.It is isostructural with RE3Co4Sn13(RE = La,Ce),featuring a 3D [Co4Sn12] framework based on [CoSn6] trigonal prisms.The [CoSn6] trigonal prisms are interconnected via corner-sharing and Sn-Sn bonds to form a 3D [Co4Sn12] framework.The other Sn and Tb atoms are located in the spacers of the 3D framework.Band structure calculations indicate that Tb3Co4Sn13 is metallic. 展开更多
关键词 INTERMETALLIC STANNIDE crystal structure band structure calculation
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Ba_2SbGaS_5 : Solid-state Synthesis, Crystal and Electronic Structures, and Property Characterization 被引量:1
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作者 耿磊 张浩 程文旦 《Chinese Journal of Structural Chemistry》 SCIE CAS CSCD 2013年第4期538-544,共7页
Single crystal of Ba2SbGaSs has been synthesized by the high temperature solidstate reaction method. The compound crystallizes in the orthorhombic space group Pnma with a = 12.177(4), b = 8.880(3), c = 8.982(3) ... Single crystal of Ba2SbGaSs has been synthesized by the high temperature solidstate reaction method. The compound crystallizes in the orthorhombic space group Pnma with a = 12.177(4), b = 8.880(3), c = 8.982(3) A, V= 971.4(6) A3, Z = 4, De = 4.284 g/cm3,μ = 14.487 mm-1, F(000) - 1096, the final R = 0.0171 and wR = 0.0384 for all data. The structure comprises an infinite one-dimensional 1∞[SbGaS5]4- anionic chain constructed from the GaS4 tetrahedra and the SbS5 polyhedra via sharing edge alternately. The paralleled 1∞[SbGaS5]4anionic chains engage with each other and form the two-dimensional Sb-Ga-S layer perpendicular to a-axis with the isolated Ba2+ cations arranged between layers. The IR spectrum and the UV-Vis spectrum have been investigated. Also, the first-principles band structure and density of states calculations indicate that the compound belongs to indirect semiconductor with the band gap of 2.1 eV, which is supported by the UV-Vis diffuse reflectance results. 展开更多
关键词 crystal structure solid-state synthesis X-ray diffraction electronic structure calculation
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Synthesis,Crystal Structure,and Optical Property of Zero-dimensional Quaternary Thioborate:Ba9B3GaS15 被引量:1
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作者 王金秋 刘鹏飞 +1 位作者 黎艳艳 吴立明 《Chinese Journal of Structural Chemistry》 SCIE CAS CSCD 2016年第12期1860-1867,共8页
A new zero-dimensional(0D) thioborate Ba_9B_3GaS_(15) has been discovered by conventional high-temperature solid-state reaction. The compound crystallizes in orthorhombic space group Pbca with a = 8.4759(8),b = ... A new zero-dimensional(0D) thioborate Ba_9B_3GaS_(15) has been discovered by conventional high-temperature solid-state reaction. The compound crystallizes in orthorhombic space group Pbca with a = 8.4759(8),b = 22.266(2),c = 31.426(3) ?,V = 5931(2) ?~3,Z = 8,Mr = 1819.11,Dc = 4.075 g/cm3,μ = 13.684 mm^(-1),F(000) = 6320,S = 1.034,(Δρ)max = 5.039,(Δρ)min = –5.409 e/?~3,the final R = 0.0362 and w R = 0.1053 for 19243 observed reflections with I 〉 2σ(I). The structure is constructed by discrete [BS_3]^(3–) trigonal planes and isolated [GaS_4]^(5–) tetrahedra with Ba^(2+) and isolated S^(2–) filled among them. The UV-Vis-near-IR spectrum reveals a wide band gap of 3.15 eV that agrees with the electronic structure calculation. 展开更多
关键词 thioborate high-temperature solid-state reaction crystal structure optical band gap electronic structure calculation
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Synthesis,Crystal Structure and Photoluminescence of a TADF Cuprous Complex 被引量:1
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作者 梁栋 贾吉慧 +2 位作者 廖建珍 余荣民 卢灿忠 《Chinese Journal of Structural Chemistry》 SCIE CAS CSCD 2017年第1期82-88,共7页
A cuprous mononuclear copper complex [Cu(adpypz)CH3CNPPh3]BF4·CH2Cl2(1, adpypz = 9,9-dimethyl-10-(6-(3-phenyl-1H-pyrazol-1-yl)pyridin-2-yl)-9,10-dihydroacridine) was synthesized and characterized by Eleme... A cuprous mononuclear copper complex [Cu(adpypz)CH3CNPPh3]BF4·CH2Cl2(1, adpypz = 9,9-dimethyl-10-(6-(3-phenyl-1H-pyrazol-1-yl)pyridin-2-yl)-9,10-dihydroacridine) was synthesized and characterized by Elemental Analysis, NMR, UV-Vis and X-ray single-crystal structure analysis. It crystallizes in triclinic, space group P1 with a = 11.3388(4), b = 13.4569(4), c = 16.2561(6) ?, α = 97.154(3), β = 92.187(3), γ = 114.119(4)°, V = 2235.38(13) ?3, Z = 2, Mr = 967.12, Dc = 1.437 g/cm^3, F(000) = 996, μ = 2.62 mm^–1, GOOF = 1.031, the final R = 0.0417, and w R = 0.1024 for 8043 observed reflections with I 〉 2σ(I). The Cu(I) atoms in the complex are four-coordinated and adopt a tetrahedral coordination geometry. In the solid state, the complex exhibits bluish-green photoluminescence with emission peaks λmax = 492 nm(1), lifetimes 235 μs and quantum yields(ф = 0.279) at room temperature. The studies of varied temperature emission spectra and decay behaviours of the complex indicate that the complex displays thermally activated delayed fluorescence(TADF) at room temperature. The results of the experimental and DFT calculations suggest that the emission in the solid state originates from the ILCT excited states. 展开更多
关键词 Cu(Ⅰ) complex crystal structure emissive property DFT calculation
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Surface for methane combustion:O(^3P)+CH4→OH+CH3
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作者 Ya Peng Zhong-An Jiang Ju-Shi Chen 《Chinese Physics B》 SCIE EI CAS CSCD 2020年第7期286-294,共9页
Kinetic investigations including quasi-classical trajectory and canonical unified statistical theory method calculations are carried out on a potential energy surface for the hydrogen-abstraction reaction from methane... Kinetic investigations including quasi-classical trajectory and canonical unified statistical theory method calculations are carried out on a potential energy surface for the hydrogen-abstraction reaction from methane by atom O(^3P).The surface is constructed using a modified Shepard interpolation method.The ab initio calculations are performed at the CCSD(T)level.Taking account of the contribution of inner core electrons to electronic correlation interaction in ab initio electronic structure calculations,modified optimized aug-cc-pCVQZ basis sets are applied to the all-electrons calculations.On this potential energy surface,the triplet oxygen atom attacks methane in a near-collinear H-CH3 direction to form a saddle point with barrier height of 13.55 kcal/mol,which plays a key role in the kinetics of the title reaction.For the temperature range of 298-2500 K,our calculated thermal rate constants for the O(^3P)+CH4→OH+CH3 reaction show good agreement with relevant experimental data.This work provides detailed mechanism of this gas-phase reaction and a theoretical guidance for methane combustion. 展开更多
关键词 methane combustion potential energy surface transition state KINETIC ab initio electronic structure calculation
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Investigation of Performance of Turret Assembly in Inboard Turret Mooring System
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作者 Ma Peisun , Ma Lie and Lu Shunshou Associate Professor, Shanghai Jiaotong University, Shanghai Graduate, Shanghai Jiaotong University, Shanghai Engineer, Shanghai Jiaotong University, Shanghai 《China Ocean Engineering》 SCIE EI 1991年第4期409-418,共10页
To fulfil the need of development of offshore oil floating production system, the performance of turret assembly in an inboard turret mooring system has been investigated in the paper. By means of systematic evaluatio... To fulfil the need of development of offshore oil floating production system, the performance of turret assembly in an inboard turret mooring system has been investigated in the paper. By means of systematic evaluation, the optimal structure of the turret for single-point mooring systems has been determined. Through model tests of a turret mooring system, several groups of data such as forces, moments and displacements under different environmental conditions have been obtained. Stresses and strains of the turret structure have been calculated by means of the finite element method corresponding to the situation in the model experiment. The study shows that the selected turret structure and the designed turret assembly are technically feasible. 展开更多
关键词 turret mooring system structure calculations finite element method turret assembly
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Synthesis, Crystal Structure and Band Structure of EuMg_6Sn_(3.67)
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作者 岳呈阳 周芳霞 +2 位作者 王明锋 张慧苹 雷晓武 《Chinese Journal of Structural Chemistry》 SCIE CAS CSCD 2013年第4期495-500,共6页
EuMg6Sn3.67 has been synthesized by reacting the mixture of the corresponding pure elements at high temperature, and structurally characterized by single-crystal X-ray diffraction study. EuMg6Sn3.67 crystallizes in he... EuMg6Sn3.67 has been synthesized by reacting the mixture of the corresponding pure elements at high temperature, and structurally characterized by single-crystal X-ray diffraction study. EuMg6Sn3.67 crystallizes in hexagonal space group P63/m (No. 176) with a = 11.7259(4), c = 4.5507(2) A, V= 541.88(4)A3 Z = 2, Mr = 734.60, Dc= 4.502 g/cm3, μ = 14.348 mm-1, F(000) = 638, the final R = 0.0128 and wR = 0.0378 for 464 observed reflections with 1 〉 2σ-(1). EuMg6Sn3.67 is closely related to the Ba2Mg2GeT.33 structure type and features a three-dimensional [Mg6Sn3.67] framework with one-dimensional hexagonal tunnels along the c-axis occupied by the Eu atoms. Electronic structure calculation indicates that the title compound is metallic. 展开更多
关键词 INTERMETALLIC STANNIDE crystal structure band structure calculation
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Electron-correlation-induced band renormalization and Mott transition in Ca_(1-x)Sr_xVO_3
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作者 王广涛 张敏平 郑立花 《Chinese Physics B》 SCIE EI CAS CSCD 2011年第9期329-333,共5页
We present the local density approximate+Gutzwiller results for the electronic structure of Cal-xSrxVOa. The substitution of Sr2+ by Ca2+ reduces the bandwidth, as the V-O-V bond angle decreases from 180° for ... We present the local density approximate+Gutzwiller results for the electronic structure of Cal-xSrxVOa. The substitution of Sr2+ by Ca2+ reduces the bandwidth, as the V-O-V bond angle decreases from 180° for SrVO3 to about 160° for CaVO3. However, we find that the bandwidth decrease induced by the V-O-V bond angle decrease is smaller as compared to that induced by electron correlation. In correlated electron systems, such as Cal-=Sr=VOa, the correlation effect of 3d electrons plays a leading role in determining the bandwidth. The electron correlation effect and crystal field splitting collaboratively determine whether the compounds will be in a metal state or in a Mort-insulator phase. 展开更多
关键词 electronic structure calculation strongly correlated system metal-insulator transition
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Role of buffer layer in electronic structures of iron phthalocyanine molecules on Au(111)
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作者 孙家涛 潘理达 +2 位作者 胡昊 杜世萱 高鸿钧 《Chinese Physics B》 SCIE EI CAS CSCD 2010年第9期25-30,共6页
We investigate the electronic structures of one and two monolayer iron phthalocyanine (FePc) molecules on Au(111) surfaces. The first monolayer FePc is lying flat on the Au(111) substrate, and the second monolay... We investigate the electronic structures of one and two monolayer iron phthalocyanine (FePc) molecules on Au(111) surfaces. The first monolayer FePc is lying flat on the Au(111) substrate, and the second monolayer FePc is tilted at -15° relative to the substrate plane along the nearest neighbour [101] direction with a lobe downward to the central hole of the unit cell in the first layer. The structural information obtained by first-principles calculations is in agreement with the experiment results. Furthermore, it is demonstrated that the electronic structures of FePc molecules in one-monolayer FePc/Au(111) system are perturbed significantly, while the electronic structures of FePc molecules in the second monolayer in two-monolayer FePc/Au(111) system remain almost unchanged due to the screening of the buffer layer on Au(111). 展开更多
关键词 iron phthalocyanine electronic structure calculations buffer layer
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