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Synthesis,Crystal Structure and Luminescent Property of a Novel Pt(Ⅱ) Complex with Weak Metal-metal Interaction
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作者 岳呈阳 江飞龙 +1 位作者 冯蕊 洪茂椿 《Chinese Journal of Structural Chemistry》 SCIE CAS CSCD 北大核心 2008年第11期1349-1352,共4页
The title complex cis-bis(tetrahydrothiophene)-bis(nitrate) platinum(H), (tht)2Pt(NO3)2, was the reducing product from potassium hexachloroplatinate(IV) K2PtC16 where the platinum is tetra-valenced. Crysta... The title complex cis-bis(tetrahydrothiophene)-bis(nitrate) platinum(H), (tht)2Pt(NO3)2, was the reducing product from potassium hexachloroplatinate(IV) K2PtC16 where the platinum is tetra-valenced. Crystal data for CsH16N206PtS2: monoclinic, space group P21/c, a = 9.8833(5), b = 8.6744(4), c = 18.6407(9)A,β = 114.401(3)°, V = 1455.35(12)A3 Z = 4, Mr = 495.44, Dc = 2.261 g/cm3, F(000) = 944,μ = 9.950 mm-1, 2(MoKa) = 0.71073 A, T= 293(2) K, 2θmax = 54.96°, GOOF = 1.033, R = 0.0350 and wR = 0.0785 for 2572 observed reflections with I 〉 2σ(I). X-ray diffraction studies reveal that the title complex has interesting weak metal-metal interactions and two molecules linked by metal-metal interaction exist as a group. Luminescent spectrum illuminates red emission of the complex at room temperature. 展开更多
关键词 metal-metal interactions REDUCING PLATINUM LUMINESCENCE
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Oscillation of Dzyaloshinskii–Moriya interaction driven by weak electric fields
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作者 陈润泽 曹安妮 +3 位作者 王馨苒 柳洋 杨洪新 赵巍胜 《Chinese Physics B》 SCIE EI CAS CSCD 2024年第2期487-491,共5页
Dzyaloshinskii–Moriya interaction(DMI) is under extensive investigation considering its crucial status in chiral magnetic orders, such as Néel-type domain wall(DW) and skyrmions. It has been reported that the in... Dzyaloshinskii–Moriya interaction(DMI) is under extensive investigation considering its crucial status in chiral magnetic orders, such as Néel-type domain wall(DW) and skyrmions. It has been reported that the interfacial DMI originating from Rashba spin–orbit coupling(SOC) can be linearly tuned with strong external electric fields. In this work, we experimentally demonstrate that the strength of DMI exhibits rapid fluctuations, ranging from 10% to 30% of its original value, as a function of applied electric fields in Pt/Co/MgO heterostructures within the small field regime(< 10-2V/nm). Brillouin light scattering(BLS) experiments have been performed to measure DMI, and first-principles calculations show agreement with this observation, which can be explained by the variation in orbital hybridization at the Co/MgO interface in response to the weak electric fields. Our results on voltage control of DMI(VCDMI) suggest that research related to the voltage control of magnetic anisotropy for spin–orbit torque or the motion control of skyrmions might also have to consider the role of the external electric field on DMI as small voltages are generally used for the magnetoresistance detection. 展开更多
关键词 Dzyaloshinskii-Moriya interaction weak electric field control effect Rashba spin-orbit coupling interfacial orbital hybridization
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Plume-lithosphere interaction in the Comei Large Igneous Province: Evidence from two types of mafic dykes in Gyangze, south Tibet, China
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作者 Ya-ying Wang Ling-sen Zeng +6 位作者 Li-e Gao Li-long Yan Ling-hao Zhao Jia-hao Gao Ying-long Di Guang-xu Li Yi-hong Tian 《China Geology》 CAS CSCD 2024年第1期80-90,共11页
Two suites of mafic dykes,T1193-A and T1194-A,outcrop in Gyangze area,southeast Tibet.They are in the area of Comei LIP and have indistinguishable field occurrences with two other dykes in Gyangze,T0902 dyke with 137.... Two suites of mafic dykes,T1193-A and T1194-A,outcrop in Gyangze area,southeast Tibet.They are in the area of Comei LIP and have indistinguishable field occurrences with two other dykes in Gyangze,T0902 dyke with 137.7±1.3 Ma zircon age and T0907 dyke with 142±1.4 Ma zircon age reported by Wang YY et al.(2016),indicating coeval formation time.Taking all the four diabase dykes into consideration,two different types,OIB-type and weak enriched-type,can be summarized.The“OIB-type”samples,including T1193-A and T0907 dykes,show OIB-like geochemical features and have initial Sr-Nd isotopic values similar with most mafic products in Comei Large Igneous Provinces(LIP),suggesting that they represent melts directly generated from the Kerguelen mantle plume.The“weak enriched-type”samples,including T1194-A and T0902 dykes,have REEs and trace element patterns showing withinplate affinity but have obvious Nb-Ta-Ti negative anomalies.They show uniform lowerεNd(t)values(−6‒−2)and higher 87Sr/86Sr(t)values(0.706‒0.709)independent of their MgO variation,indicating one enriched mantle source.Considering their closely spatial and temporal relationship with the widespread Comei LIP magmatic products in Tethyan Himalaya,these“weak enriched-type”samples are consistent with mixing of melts from mantle plume and the above ancient Tethyan Himalaya subcontinental lithospheric mantle(SCLM)in different proportions.These weak enriched mafic rocks in Comei LIP form one special rock group and most likely suggest large scale hot mantle plume-continental lithosphere interaction.This process may lead to strong modification of the Tethyan Himalaya lithosphere in the Early Cretaceous. 展开更多
关键词 OIB type diabase Comei Large Igneous Province weakly enriched diabase Plume-lithosphere interaction Nb-Ta-Ti negative anomaly Kerguelen plume Geological survey engineering Tibet Plateau
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Dicobalt Complex with Metal-metal Interaction of a Naphthyridine and Pyrazine Amine Ligand
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作者 GENG Shu-Bo WANG Wen-Zhen +4 位作者 LI Lei-Lei JIA Xin-Gang LIU Shuang Gene-Hsiang Lee Shie-Ming Peng 《Chinese Journal of Structural Chemistry》 SCIE CAS CSCD 2017年第6期1011-1019,共9页
Molecular structure of a naphthyridine and pyrazine amine ligand, N2,N7-di(pyrazin-2-yl)-1,8-naphthyri-dine-2,7-diamine(H2dpznda 1) was studied, and a three-dimensional supramolecular network with a double helix c... Molecular structure of a naphthyridine and pyrazine amine ligand, N2,N7-di(pyrazin-2-yl)-1,8-naphthyri-dine-2,7-diamine(H2dpznda 1) was studied, and a three-dimensional supramolecular network with a double helix chain structure through intermolecular hydrogen bonds and π-π interactions between the naphthyridine and pyrazine rings was depicted. Through ligand 1, [Co2(μ2-dpznda)2(μ2-CH3OH)2](2) was obtained and two ligands coordinate to two Co2+)as tetradentate bridging ligands. Single crystal and magnetism study on 2 revealed that the complex exhibited weak yet significant metal-metal interaction. 展开更多
关键词 metal-metal interaction cobalt-cobalt bond hydrogen bonds π-π interaction magnetic property
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A 3-D Hybrid Framework {[(dafone)PbI_2](dafone)_2}_n Constructed from Weak Interactions by Introducing Aromatic H-bond Acceptors: Synthesis and Theoretical Study 被引量:2
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作者 李俊波 李浩宏 +3 位作者 陈之荣 陈小波 吴艳玲 董海军 《Chinese Journal of Structural Chemistry》 SCIE CAS CSCD 2009年第11期1387-1392,共6页
A new 3-D hybrid framework {[(dafone)PbI2](dafone)2}n 1 (dafone = 4,5-diazafluoren-9-one) has been prepared and structurally determined. 1 crystallizes in the monoclinic system, space group C2/c with a = 24.109... A new 3-D hybrid framework {[(dafone)PbI2](dafone)2}n 1 (dafone = 4,5-diazafluoren-9-one) has been prepared and structurally determined. 1 crystallizes in the monoclinic system, space group C2/c with a = 24.109(8), b = 16.596(8), c = 7.983(3)A, β = 91.590(15)°, V = 3193(2)A^3, Z = 4, C33H18I2N6O3Pb, Mr = 1007.53, Dc = 2.096 g/cm^3, F(000) = 1880, μ(MoKα) = 7.262 mm^-1, the final R = 0.0352 and wR = 0.0951 for 3198 observed reflections with I 〉 2σ(I). In the [(dafone)PbI2]n chain, the Pb center adopts a distorted octahedral coordination geometry and shares an edge to give a one-dimensional polymer. The 3-D arrangement of 1 constructs from H-bonds among dafone molecules and π-π stacking interactions among dissociative dafone molecules. These weak interactions contribute to the stability of the title compound. DFT calculation was carried out to reveal its electronic structure. 展开更多
关键词 dafone weak interactions aromatic hydrogen bond acceptors DFT calculation
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Interesting Weak Interactions in Three Silver Coordination Polymers Based on Tetrafluorobenzenedicarboxylate and Benzonitrile Ligands 被引量:2
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作者 刘淑芹 李晓娟 +2 位作者 狄玲 丁保君 张建军 《Chinese Journal of Structural Chemistry》 SCIE CAS CSCD 2013年第7期969-974,共6页
The assembly reactions of o- (or m-, or p-) tetrafluorobenzenedicarboxylic acid (denoted as o-H2L, m-H2L and p-HzL, respectively), benzonitrile and Ag+ ion led to three compounds: [Ag2(PhCN)2(o-HL)2]n (1),... The assembly reactions of o- (or m-, or p-) tetrafluorobenzenedicarboxylic acid (denoted as o-H2L, m-H2L and p-HzL, respectively), benzonitrile and Ag+ ion led to three compounds: [Ag2(PhCN)2(o-HL)2]n (1), [Ag2(PhCN)2(m-HL)2]n (2) and [Ag2(PhCN)2(p-L)], (3). 1 and 2 feature a 1D coordination chain, while 3 bears a 2D net structure. A variety of weak interactions are observed in the compounds. Strong nwrinteractions connect the 1D chains into a 3D supramolecular network in 1. Hydrogen bonds connect the chains into layers in 2. Three types of interesting π-π interactions also assemble the 2D layers into a 3D overall structure in 3. 展开更多
关键词 coordination polymers crystal structure weak interactions
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The Weak Interaction on CO_2...CO van der Waals Complex: A Theoretical Study 被引量:1
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作者 CAO Zhao-hua +2 位作者 BU Yu-xiang 《Chemical Research in Chinese Universities》 SCIE CAS CSCD 2003年第1期94-99,共6页
The geometries of van der Waals complex CO 2...CO were optimized at DFT and second order Moller Plesset perturbation(MP2) levels with the large basis set, three stable structures were found. The most stable structu... The geometries of van der Waals complex CO 2...CO were optimized at DFT and second order Moller Plesset perturbation(MP2) levels with the large basis set, three stable structures were found. The most stable structure has a T shape geometry in which the CO lies along the C 2 axis of CO 2, with the two C atoms direct contact and R (C...C)=0 3227 nm. The corresponding energies of the most stable structure were calculated by means of MP2, MP4D, MP4DQ, MP4SDTQ, MP4SDQ, CCSD and CCSD(T) methods. The BSSE(basis set superposition error) was eliminated by the Boys Bernardi counterpoise correction(CP) method. According to thermodynamics data, van der Waals complex CO 2...CO can be found at a low temperature and/or a high pressure. There is a little charge transferred between the two interacted subunits. In the most stable structure, CO 2 is the acceptor and CO is the donor. 展开更多
关键词 CO 2...CO van der Waals complex weak interaction MP2 calculation DFT calculation
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Characteristics of lateral vehicular interactions in heterogeneous traffic with weak lane discipline 被引量:1
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作者 Anuj Kishor Budhkar Akhilesh Kumar Maurya 《Journal of Modern Transportation》 2017年第2期74-89,共16页
Heterogeneous traffic conditions prevail in developing countries. Vehicles maintain weak lane discipline which increases lateral interactions of vehicles significantly. It is necessary to study these interactions in t... Heterogeneous traffic conditions prevail in developing countries. Vehicles maintain weak lane discipline which increases lateral interactions of vehicles significantly. It is necessary to study these interactions in the form of maintained lateral gaps for modeling this traffic scenario. This paper aims at determining lateral clearances maintained by different vehicle types while moving in a heterogeneous traffic stream during overtaking. These data were collected using an instrumented vehicle which runs as a part of the stream. Variation of obtained clearance with average speed of interacting vehicles is studied and modeled. Different instrumented vehicles of various types are developed using (1) ultrasonic sensors fixed on both sides of vehicle, which provide inter-vehicular lateral distance and relative speed; and (2) GPS device with cameras, which provides vehicle type and speed of interacting vehicles. They are driven on different roads in six cities of India, to measure lateral gaps maintained with different interacting vehicles at different speeds. Relationships between lateral gaps and speed are modeled as regression lines with positive slopes and beta-distributed residuals. Nature of these graphs (i.e., slopes, intercepts, residuals) are also evaluated and compared for different interacting vehicle-type pairs. It is observed that similar vehicle pairs maintain less lateral clearance than dissimilar vehicle pairs. If a vehicle interacts with two vehicles (one on each side) simultaneously, lateral clearance is reduced and safety of the vehicles is compromised. The obtained relationships can be used for simulating lateral clearance maintaining behavior of vehicles in heterogeneous traffic. 展开更多
关键词 Ultrasonic sensors - Heterogeneous traffic Lateral gaps Lateral vehicular interactions weak lane discipline
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Weak Interaction and the Nature of Virtual Particles 被引量:1
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作者 Vladimir Konushko 《Journal of Modern Physics》 2011年第2期45-57,共13页
The granular structure of space, the nature of virtual particles and the unity of physical interactions are under study. The mass of an elementary cell in the Universe is determined, as a whole, with the physical mean... The granular structure of space, the nature of virtual particles and the unity of physical interactions are under study. The mass of an elementary cell in the Universe is determined, as a whole, with the physical meaning of the renormalization procedure changing in this case. 展开更多
关键词 weak interaction
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One-dimensional Chain Topology in [Ag(C_6H_6NCl)_2](ClO_4), Generated through Weak Interaction between Molecules
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作者 孙道峰 曹荣 +2 位作者 梁玉仓 洪茂椿 苏伟平 《Chinese Journal of Structural Chemistry》 SCIE CAS CSCD 北大核心 2001年第3期165-167,共3页
The mononuclear complex [Ag(C6H6NCl)2](ClO() has been prepared and structurally analyzed by single-crystal X-ray diffraction. The complex crystallizes in the monoclinic system, space group C2/c with unit cell paramete... The mononuclear complex [Ag(C6H6NCl)2](ClO() has been prepared and structurally analyzed by single-crystal X-ray diffraction. The complex crystallizes in the monoclinic system, space group C2/c with unit cell parameters: a=15.5314(2), b=8.0247(8), c=15.3701(2)?.β=118.832(2)°, V=1678.2(3)?3, Z=4, Mr=462.46, Dc=1.830Mg/m3, F(000)=912, μ(MoKα) = 1.694cm-1. The final R and wR are 0.0472 and 0.1272 for 1484 observed reflections with I≥3σ(I). The Ag atom is coordinated by two nitrogen atoms of 4-chloromethyl-pyridine in a linear coordination geometry. Each molecule is further linked by the weak interaction between the Cl and Ag atoms to form a one-dimensional chain structure with Ag-Cl distance of 3.240?. 展开更多
关键词 MONONUCLEAR linear weak interaction ONE-DIMENSION
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ON WEAK MINIMUM ABERRATION AND NUMBER OF CLEAR TWO-FACTOR INTERACTION COMPONENTS IN s_Ⅳ~(m-p) DESIGNS
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作者 杨贵军 《Acta Mathematica Scientia》 SCIE CSCD 2010年第1期240-246,共7页
This article obtains some theoretical results on the number of clear two-factor interaction components and weak minimum aberration in an sm-pIVdesign, by considering the number of not clear two-factor interaction comp... This article obtains some theoretical results on the number of clear two-factor interaction components and weak minimum aberration in an sm-pIVdesign, by considering the number of not clear two-factor interaction components of the design. 展开更多
关键词 clear two-factor interaction component weak minimum aberration resolu-tion wordlength pattern
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Weak Interactions and 2D Layer Structure of a New Ion-pair Complex Bis(1-benzyl-4-methylquinolinium)-bis(maleonitriledithiolato)nickel(Ⅱ)
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作者 周家容 倪春林 《Chinese Journal of Structural Chemistry》 SCIE CAS CSCD 北大核心 2007年第11期1263-1266,共4页
A new ion-pair complex, [BzMeQ1]2[Ni(nmt)2]1([BzMeQ1]^+ = 1-benzyl-4-ntethylquino- linium, mnta- -- maleonitriledithiolate) has been synthesized and structurally characterized by IR, ESI-MS and X-ray diffraction ... A new ion-pair complex, [BzMeQ1]2[Ni(nmt)2]1([BzMeQ1]^+ = 1-benzyl-4-ntethylquino- linium, mnta- -- maleonitriledithiolate) has been synthesized and structurally characterized by IR, ESI-MS and X-ray diffraction methods. Complex 1 is of triclinic, space group PI, with a = 9.079(2), b = 10.154(2), c = 11.243(2)A, α= 81.58(1), β= 69.63(1), γ = 68.02(1)°, V= 940.1(3)A3, Dc = 1.427 g/cm^3, Z = 1, F(000) = 418 and R = 0.0442. A 2D layer structure is formed via the cation-cation π…π and C-H…π interactions observed in the solid state of the complex. 展开更多
关键词 1-benzyl-4-methylquinolinium bis (maleonitriledithiolate)nickclatc(Ⅱ) complex weak interactions 2D layer structure
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Spin-Spin Interactions in Gauge Theory of Gravity, Violation of Weak Equivalence Principle and New Classical Test of General Relativity 被引量:1
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作者 WU Ning 《Communications in Theoretical Physics》 SCIE CAS CSCD 2008年第6期1533-1540,共8页
很长时间,纺纱纺纱相互作用能仅仅在 Lorentz 对称被计量的一个理论存在,这通常 perturbatively 被相信了,并且有纺纱纺纱相互作用的一个理论不是 renormalizable。但是这不是真的。由在重力的地里学习一个旋转粒子的运动,在那里存... 很长时间,纺纱纺纱相互作用能仅仅在 Lorentz 对称被计量的一个理论存在,这通常 perturbatively 被相信了,并且有纺纱纺纱相互作用的一个理论不是 renormalizable。但是这不是真的。由在重力的地里学习一个旋转粒子的运动,在那里存在,这被发现在严肃的计量器理论的纺纱纺纱相互作用。它的机制是一个旋转粒子将产生 gravitomagnetic 在时空的地,和这个 gravitomagnetic 领域将与另一个粒子的旋转交往,它将引起纺纱纺纱相互作用。那么,纺纱纺纱相互作用由重力的地被播送。在柱子的纺纱纺纱相互作用的表格牛顿的近似被推出。这结果能也从 Papapetrou 方程被推出。这种相互作用不影响理论的 renormalizability。纺纱纺纱相互作用将违背弱等价原则,并且违背效果是可检测的。一个实验被建议检测弱等价原则的违背的效果。 展开更多
关键词 自旋交互作用 弱等价原则 自旋颗粒运动 重力理论
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WEAK SOLUTION TO THE INCOMPRESSIBLE VISCOUS FLUID AND A THERMOELASTIC PLATE INTERACTION PROBLEM IN 3D
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作者 Srdan TRIFUNOVIC 王亚光 《Acta Mathematica Scientia》 SCIE CSCD 2021年第1期19-38,共20页
In this paper we deal with a nonlinear interaction problem between an incompressible viscous fluid and a nonlinear thermoelastic plate.The nonlinearity in the plate equation corresponds to nonlinear elastic force in v... In this paper we deal with a nonlinear interaction problem between an incompressible viscous fluid and a nonlinear thermoelastic plate.The nonlinearity in the plate equation corresponds to nonlinear elastic force in various physically relevant semilinear and quasilinear plate models.We prove the existence of a weak solution for this problem by constructing a hybrid approximation scheme that,via operator splitting,decouples the system into two sub-problems,one piece-wise stationary for the fluid and one time-continuous and in a finite basis for the structure.To prove the convergence of the approximate quasilinear elastic force,we develop a compensated compactness method that relies on the maximal monotonicity property of this nonlinear function. 展开更多
关键词 fluid-structure interaction incompressible viscous fluid nonlinear thermoelastic plate three space variables weak solution
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NMR STUDIES ON THE WEAK INTERACTION OF FOUR-MONONUCLEOTIDES WITH TRYPTAMIDE AND LEUCINAMIDE
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作者 Wen Qing WANG Xiang DING +4 位作者 Jian JIANG Guang Zhong TU Li Bin MA Shao Liang HONG 《Chinese Chemical Letters》 SCIE CAS CSCD 1993年第5期431-434,共4页
NMR spectroscopy analysis was introduced to investigate the weak interaction of four 5'—mononucleotides with tryptamide and leucinamide. Assuming a 1∶1 complex formation, the association constants were determine... NMR spectroscopy analysis was introduced to investigate the weak interaction of four 5'—mononucleotides with tryptamide and leucinamide. Assuming a 1∶1 complex formation, the association constants were determined by nonlinear regression analysis. The association affinity of 4 mononucleotides with tryptamide decreased in the order: G>A>C>U, indicating that purine bases stack more strongly with tryptamide than pyrimidine bases. But with leucinamide the affinity decreases in the order: G>C>A=U, suggesting an amino acid—anticodonic preferential interaction. The implication of the present data to the origin of genetic code was briefly discussed. 展开更多
关键词 NMR STUDIES ON THE weak interaction OF FOUR-MONONUCLEOTIDES WITH TRYPTAMIDE AND LEUCINAMIDE
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INTERACTION OF STRONG AND WEAK SINGULARITIES FOR HYPERBOLIC SYSTEM OF CONSERVATION LAWS IN MULTIDIMENSIONAL SPACE
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作者 陈恕行 《Acta Mathematica Scientia》 SCIE CSCD 1990年第3期298-302,共5页
In this paper we study the interaction of strong and weak singularities for hyperbolic system of conservation laws in multidimensional space. Under the assumption of transversal intersect of the shock front with the b... In this paper we study the interaction of strong and weak singularities for hyperbolic system of conservation laws in multidimensional space. Under the assumption of transversal intersect of the shock front with the bicharacteristics bearing weak singularities we proved a theorem on regularity propagation across the shock front. 展开更多
关键词 interaction OF STRONG AND weak SINGULARITIES FOR HYPERBOLIC SYSTEM OF CONSERVATION LAWS IN MULTIDIMENSIONAL SPACE
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Selection Rules in Weak Interaction and Conservation of Fermion Quantum Number
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作者 Xinhua Ma 《Journal of Modern Physics》 2022年第5期700-706,共7页
Traditionally, in weak interaction, I<sub>3</sub>, Y and four flavour quantum numbers are not conserved but several empirical selection rules work well. Recently, it was found that, in weak interaction, th... Traditionally, in weak interaction, I<sub>3</sub>, Y and four flavour quantum numbers are not conserved but several empirical selection rules work well. Recently, it was found that, in weak interaction, there are three levels of conservation of additive quantum numbers, and fermion quantum number F is conserved in all kinds of interactions. It is known that weak interaction has three types: fermionic, pure hadronic and pure leptonic, corresponding to the first and the second level of conservation of additive quantum numbers respectively. It is demonstrated in this paper that the selection rules in all types of weak interaction can be interpreted by conservation of F, and the formula of relation between Q/e, F and F<sub>0</sub> is more general than Gell-Mann-Nishijima formula. Description of weak interaction becomes simpler, If only we take Q, F<sub>0</sub> and F, based on the conserved physical quantities. 展开更多
关键词 weak interaction Selection Rules Fermion Quantum Number
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Three Clifford Algebras for Four Kinds of Interactions 被引量:1
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作者 Claude Daviau Jacques Bertrand 《Journal of Modern Physics》 2016年第9期936-951,共16页
Three Clifford algebras are sufficient to describe all interactions of modern physics: The Clifford algebra of the usual space is enough to describe all aspects of electromagnetism, including the quantum wave of the e... Three Clifford algebras are sufficient to describe all interactions of modern physics: The Clifford algebra of the usual space is enough to describe all aspects of electromagnetism, including the quantum wave of the electron. The Clifford algebra of space-time is enough for electro-weak interactions. To get the gauge group of the standard model, with electro-weak and strong interactions, a third algebra is sufficient, with only two more dimensions of space. The Clifford algebra of space allows us to include also gravitation. We discuss the advantages of our approach. 展开更多
关键词 GEOMETRY Invariance Group Dirac Equation Electromagnetism weak interactions Strong interactions Clifford Algebras GRAVITATION
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Crystal Structure and Interaction with DNA of [Ni(phen)(mal)(H_2O)_2]·3H_2O
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作者 高恩君 程卯生 +1 位作者 于影 孙亚光 《Chinese Journal of Structural Chemistry》 SCIE CAS CSCD 北大核心 2007年第1期59-62,共4页
A new complex [Ni(phen)(mal)(H2O)2]·3H2O (phen = 1,10-phenanthroline, real^2- = malonic acid) has been synthesized by the reaction of nickel nitrate, phen and malonic acid. EA, IR spectra and X-ray single... A new complex [Ni(phen)(mal)(H2O)2]·3H2O (phen = 1,10-phenanthroline, real^2- = malonic acid) has been synthesized by the reaction of nickel nitrate, phen and malonic acid. EA, IR spectra and X-ray single-crystal diffraction were carried out to determine the composition and crystal structure of the title complex. Crystal data: monoclinic system, space group P2/c,α = 8.937(3), b = 12.163(5), c = 9.725(3) A,β = 119.36°, C15H19N2O9Ni,Mr= 430.03, Z = 2, F(000) = 446, V= 921.3 A3, Dc = 1.550 g/cm^3, μ= 1.104 mm^-1, -10≤h≤10, -12≤k≤ 14, -11≤1≤7, R = 0.0261 and wR = 0.0609 for 4376 (Rint = 0.0203) independent reflections and 1631 observed ones (I 〉 2σ(I)). Ni(Ⅱ) exhibits an octahedral coordination geometry, with hydrogen bonds and π-π interactions stabilizing the whole structure. UV spectrum of the complex interacting with protamine DNA indicates that the title compound interacts with DNA via insertion mode with bonding constant Kb of 1. 11 × 10^4. 展开更多
关键词 Ni( molecular structure weak interaction DNA
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Quantum Chemistry Studies on the Fe-Cu Interactions and ^(31)P NMR in Fe(CO)_3(Ph_2Ppy)_2(CuX_n) (X_n=Cl_2^(2-),Cl^-,Br^-)
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作者 许旋 李勤瑜 +2 位作者 方亮 孙世玲 苏忠民 《Chinese Journal of Structural Chemistry》 SCIE CAS CSCD 北大核心 2008年第11期1339-1348,共10页
In order to study the Fe-Cu interactions and their effects on 31p NMR, the structures of mononuclear complex Fe(CO)3fPhzPpy)a 1 and binuclear complexes Fe(CO)3(PhEPpy)z(CuXn) (2: Xn = Cl2^2-, 3: Xn = Cl-, ... In order to study the Fe-Cu interactions and their effects on 31p NMR, the structures of mononuclear complex Fe(CO)3fPhzPpy)a 1 and binuclear complexes Fe(CO)3(PhEPpy)z(CuXn) (2: Xn = Cl2^2-, 3: Xn = Cl-, 4: Xn = Br-) are calculated by density functional theory (DFT) PBE0 method. For complexes 1, 3 and 4, the 31p NMR chemical shifts calculated by PBE0-GIAO method are in good agreement with experimental results. The 31p chemical shift is 82.10 ppm in the designed complex 2. The Fe-Cu interactions (including Fe→Cu and Fe←Cu charge transfer) mainly exhibit the indirect interactions. Moreover, the Fe-Cu(I) interactions (mostly acting as σFe-p→4Scu and aFe-C→4Scu charge transfer) in complexes 3 and 4 are stronger than Fe-Cu(Ⅱ) interactions (mostly acting as σFe-p→4Scu and σFe-p←4Sc,) in complex 2. In complex 2, the stronger Fe←Cu interac- tions, acting as σFe-p←44SCu charge transfer, increase the electron density on P nucleus, which causes the upfield 31p chemical shift compared with mononuclear complex 1. For 3 and 4, although a little deshielding for P nucleus is derived from the delocalization of σFe-p→4Scu due to the Fe→Cu interactions, the stronger σFe-c→np charge-transfer finally increases the electron density on P nucleus. As a result, an upfield 31p chemical shift is observed compared with 1. The stability follows the order of 2〉3=4, indicating that Fe(CO)3(PhzPpy)2(CuCl2) is stable and could be synthesized experimentally. The N-Cu(Ⅱ) interaction plays an important role in the stability of 2. Because the delocalization of σFe-p→4SCu and σFe-c→πc-o weakens the a bonds of Fe-C and ~r bonds of CO, it is favorable for increasing the catalytic activity of binuclear complexes. Complexes 3 and 4 are expected to show higher catalytic activity compared to 2. 展开更多
关键词 DFT (PBE0) GIAO 31p NMR metal-metal interaction
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