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“原子-分子”论的创立及其对我们的启迪 被引量:6
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作者 张玉春 《化学教育》 CAS 北大核心 2009年第12期81-84,共4页
“原子-分子”论在近代化学史上是一项划时代的成就,它的创立过程是在曲折中前进的。道尔顿的原子论为科学的“原子-分子”论奠定了基石,揭开了近代化学新时期的序幕。道尔顿与盖·吕萨克的学术争论主要是围绕道尔顿原子论自身存... “原子-分子”论在近代化学史上是一项划时代的成就,它的创立过程是在曲折中前进的。道尔顿的原子论为科学的“原子-分子”论奠定了基石,揭开了近代化学新时期的序幕。道尔顿与盖·吕萨克的学术争论主要是围绕道尔顿原子论自身存在的内在矛盾及其外化的“半个原子”问题而展开的,它构成了近代“原子-分子”论创立过程中的一个重要环节。阿伏加德罗在道尔顿原子论基础上提出的分子学说,初步解决了道尔顿原子论的内在矛盾及其外化的“半个原子”问题,使科学的“原子-分子”论趋于完善。坎尼扎罗“原子-分子”论的最终确立,是道尔顿原子论与阿伏加德罗分子学说有机整合的结果。“原子-分子”论的这一创立过程给予我们的启迪是深刻的,它展示了科学理论的曲折发展、“继承-创新”辩证发展、内在矛盾动力、内在矛盾外化等发展规律。 展开更多
关键词 “原子-分子”论 原子 分子学说 科学理论 发展规律 道尔顿
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Non-additivity of Methyl Group in the Single-electron Lithium Bond of H3C… Li-H Complex
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作者 李志锋 施小宁 +2 位作者 刘艳芝 唐慧安 张俊彦 《Chinese Journal of Chemical Physics》 SCIE CAS CSCD 2009年第3期303-309,340,共8页
The non-additivity of the methyl groups in the single-electron lithium bond was investigated using ab initio calculations at the B3LYP/6-311++G** and UMP2/6-311++G** levels. The strength of the interaction in ... The non-additivity of the methyl groups in the single-electron lithium bond was investigated using ab initio calculations at the B3LYP/6-311++G** and UMP2/6-311++G** levels. The strength of the interaction in the H3C… LiH, H3CH2C… LiH, (H3C)2HC… LiH, and u v (H3C)3C… LiH complexes was analyzed in term of the geometries, energies, frequency shifts, stabilization energies, charges, and topological parameters. It is shown that (H3C)3C radical with LiH forms the strongest single-electron lithium bond, followed by (H3C)2HC radical, then H3CH2C radical, and H3C radical forms the weakest single-electron lithium bond. A positive non-additivity is present among methyl groups. Natural bond orbital and atoms in molecules analyses were used to estimate such conclusions. Furthermore, there are few linear/nonlinear relationships in the system and the interaction mode of single-electron Li- bond is different from the single-electron H-bond and single-electron halogen bond. 展开更多
关键词 Single-electron lithium bond Single-electron hydrogen bond Single-electronhalogen bond MP2 Natural bond orbital Atoms in molecules
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Determination of thermodynamic properties in full composition range of Ti-Al binary melts based on atom and molecule coexistence theory 被引量:1
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作者 Sheng-chao DUAN Xiao SHI +2 位作者 Wen-sheng YANG Han-jie GUO Jing GUO 《Transactions of Nonferrous Metals Society of China》 SCIE EI CAS CSCD 2018年第6期1256-1264,共9页
The results of predicting thermodynamic properties in the full composition range of Ti-Al binary melts in a temperature range from 1973 to 2273 K were obtained by coupling with the developed thermodynamic model for ca... The results of predicting thermodynamic properties in the full composition range of Ti-Al binary melts in a temperature range from 1973 to 2273 K were obtained by coupling with the developed thermodynamic model for calculating mass action concentration N_i of structural units in Ti-Al system based on the atom and molecule coexistence theory(AMCT). Temperature dependence of the activity coefficients of Ti and Al in natural logarithmic form in the infinitely dilute solution(0x_(Ti)0.01) of Ti-Al binary melts was also determined from the calculated activity coefficients of Ti and Al at temperatures of 1973, 2073, 2173, and 2273 K. The standard molar Gibbs free energy change of dissolving pure liquid element i(l) for forming 1%(mass fraction) element i in Ti-Al binary melts further was deduced. With the aid of this model, meanwhile, the determined excess thermodynamic properties, such as the excess molar mixing Gibbs free energy/entropy/enthalpy were also calculated. 展开更多
关键词 Ti-Al binary system Ti Al activity coefficient thermodynamic model mass action concentration atom and molecule coexistence theory
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Hydrogen Bonding Character Between the Glycine and BF4^-
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作者 Qin He Jing Yang Xiang-jun Meng 《Chinese Journal of Chemical Physics》 SCIE CAS CSCD 2009年第5期517-522,I0002,共7页
The hydrogen bonding character between the BF4- and glycine was theoretically studied at the level of B3LYP/6-31+G^*, single point energies were performed at the level of B3LYP/6-311++G^**. The relevant geometri... The hydrogen bonding character between the BF4- and glycine was theoretically studied at the level of B3LYP/6-31+G^*, single point energies were performed at the level of B3LYP/6-311++G^**. The relevant geometrical characteristics, energy properties, as well as the characters of the intramolecular hydrogen bonds have been studied. Atoms in molecule theory topological analysis indicated the (3,-1) critical points for hydrogen bonds. In addition, the electron density and Laplacian were in the range suggested for the hydrogen bonds. Especially, the changes of atomic charge, hydrogen upon hydrogen bonds formation dipole moment, enegry as well as volume of the were systemitically discussed. 展开更多
关键词 B3LYP BF4^- Glycine hydrogen bond Atoms in molecule theory
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Splitting of Spectra in Anharmonic Oscillators Described by Kratzer Potential Function
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作者 Irina Petreska Trifce Sandev +1 位作者 Gjorgji Ivanovski Ljupo Pejov 《Communications in Theoretical Physics》 SCIE CAS CSCD 2010年第7期138-142,共5页
A perturbation theory model that describes splitting of the spectra in highly symmetrical molecular species in electrostatic field is proposed. An anahrmonie model of a two-dimensional oscillator having Kratzer potent... A perturbation theory model that describes splitting of the spectra in highly symmetrical molecular species in electrostatic field is proposed. An anahrmonie model of a two-dimensional oscillator having Kratzer potential energy function is used to model the molecular species and to represent the unperturbed system. A selection rule for the radial quantum number of the oscillator is derived. The eigenfunctions of a two-dimensional anharmonic oscillator in cylindrical coordinates are used for the matrix elements representing the probability for energy transitions in dipole approximation to be calculated. Several forms of perturbation operators are proposed to model the interaction between the polyatomic molecular species and an electrostatic field. It is found that the degeneracy is removed in the presence of the electric field and spectral splitting occurs. Anharmonic approximation for the unperturbed system is more accurate and reliable representation of a reaJ polyatomic molecular species. 展开更多
关键词 two-dimensional anharmonic oscillator Kratzer potential DEGENERACY selection rules PERTURBATION
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Formation Mechanism and Binding Energy for Regular Octahedral Structure of Li_6 Cluster
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作者 ZHAO Yan-Ping LI Ping GOU Qing-Quan LIU Wei-Na 《Communications in Theoretical Physics》 SCIE CAS CSCD 2008年第12期1407-1410,共4页
The formation mechanism for the regular octahedral structure of Liscluster is proposed. The curve of the total energy versus the separation R between any two neighboring nuclei has been calculated by using the method ... The formation mechanism for the regular octahedral structure of Liscluster is proposed. The curve of the total energy versus the separation R between any two neighboring nuclei has been calculated by using the method of Gou's modified arrangement channel quantum mechanics (MACQM). The result shows that the curve has a minimal energy of -44.736 89 a.u. at R = 5.07a0. When R approaches infinity, the total energy of six lithium atoms has the value of -44.568 17 a.u. So the binding energy of Li6 with respect to six lithium atoms is 0.1687 a.u. Therefore, the binding energy per atom for Li6 is 0.028 12 a.u., or 0.7637 eV, which is greater than the binding energy per atom of 0.453 eV for Li2 and the binding energy per atom of 0.494 eV for Li3 calculated in our previous work. This means that the Li6 cluster may be formed in a regular octahedral structure with a greater binding energy. 展开更多
关键词 Li6 cluster formation mechanism binding energy
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On the Bonding Nature of Noble Gas Compounds MRg^(+) and MRgF(M=Co,Rh,Ir;Rg=Ar,Kr,Xe)
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作者 Si-yuan Xian Di-hao Tan An-yong Li 《Chinese Journal of Chemical Physics》 SCIE CAS CSCD 2021年第3期297-308,I0039-I0043,I0047,共18页
The structure and stability of the compounds MRg^(+)and MRg F(Rg=Ar,Kr,and Xe;M=Co,Rh,and Ir)were investigated using the B3 LYP,MP2,MP4(SDQ)and CCSD(T)methods.We reported the geometry,vibrational frequencies and therm... The structure and stability of the compounds MRg^(+)and MRg F(Rg=Ar,Kr,and Xe;M=Co,Rh,and Ir)were investigated using the B3 LYP,MP2,MP4(SDQ)and CCSD(T)methods.We reported the geometry,vibrational frequencies and thermodynamics properties of these compounds.A series of theoretical methods on the basis of wavefunction analysis,including natural bond orbitals,atoms in molecules,electron localization function,and energy decomposition analysis,were performed to explore bonding nature of the M-Rg and Rg-F bonds.These bonds are mainly noncovalent,the metal weakly interacts with Rg in MRg^(+),but their interaction is much stronger in MRg F.The neutral molecule MRg F can be well described by the Lewis structure[MRg]^(+)F^(-). 展开更多
关键词 Rare gases CO RH IR Bond nature Natural bond orbitals Atom in molecules analyses Electron localization function analyses
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A Note on Normal Forms of Quantum States and Separability
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作者 LI Ming FEI Shao-Ming WANG Zhi-Xi 《Communications in Theoretical Physics》 SCIE CAS CSCD 2008年第12期1307-1311,共5页
We study the normal form of multipartite density matrices.It is shown that the correlation matrix(CM)separability criterion can be improved from the normal form we obtained under filtering transformations.Based on CMc... We study the normal form of multipartite density matrices.It is shown that the correlation matrix(CM)separability criterion can be improved from the normal form we obtained under filtering transformations.Based on CMcriterion the entanglement witness is further constructed in terms of local orthogonal observables for both bipartite andmultipartite systems. 展开更多
关键词 separable state entanglement witness
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Generalized Morrey spaces and trace operator 被引量:6
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作者 NAKAMURA Shohei NOI Takahiro SAWANO Yoshihiro 《Science China Mathematics》 SCIE CSCD 2016年第2期281-336,共56页
The theory of generalized Besov-Morrey spaces and generalized Triebel-Lizorkin-Morrey spaces is developed. Generalized Morrey spaces, which Mizuhara and Nakai proposed, are equipped with a parameter and a function. Th... The theory of generalized Besov-Morrey spaces and generalized Triebel-Lizorkin-Morrey spaces is developed. Generalized Morrey spaces, which Mizuhara and Nakai proposed, are equipped with a parameter and a function. The trace property is one of the main focuses of the present paper, which will clarify the role of the parameter of generalized Morrey spaces. The quarkonial decomposition is obtained as an application of the atomic decomposition. In the end, the relation between the function spaces dealt in the present paper and the foregoing researches is discussed. 展开更多
关键词 Morrey space trace operator DECOMPOSITION
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Manipulating Photoelectron Distributions for Rare Gas Atoms Ionized with Polarized Femtosecond Laser Pulses
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作者 李小刚 《Communications in Theoretical Physics》 SCIE CAS CSCD 2012年第6期1053-1058,共6页
Above-threshold ionizations of rare gas atoms excited by polarized femtosecond laser pulses are investigated.The photoelectron momentum spectra are obtained applying the strong-field approximation(SFA) theory.It is fo... Above-threshold ionizations of rare gas atoms excited by polarized femtosecond laser pulses are investigated.The photoelectron momentum spectra are obtained applying the strong-field approximation(SFA) theory.It is found that,distribution of the emitted photoelectrons varies with different polarizations of laser pulses.We have interpreted the relationship between the observed distribution and the laser polarization taking advantage of tunneling ionization theory and simple-man model.The polarization sensitivity indicates that one can easily manipulate the photoelectron distribution by controlling the polarization of the exciting pulse. 展开更多
关键词 above-threshold ionization femtosecond laser strong-field approximation
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Structural and Interaction Properties of Porphyrin Layers — A Quantum Chemical Study
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作者 G.Praveena A.Abiram 《Communications in Theoretical Physics》 SCIE CAS CSCD 2015年第5期625-634,共10页
This paper is proposed to understand the interaction of porphyrin layers with diatomic molecules interacting at their interior regions by applying ab initio and density functional theory (DFT) methods. We have used ... This paper is proposed to understand the interaction of porphyrin layers with diatomic molecules interacting at their interior regions by applying ab initio and density functional theory (DFT) methods. We have used NO, GO, and O2 diatomic molecules to interact with the porphyrin layers. The most common Fe-centered metalloporphyrin structure with tetra-pyrrlic rings having N4 core is chosen for the study. The optimization of Porphyrin-Porphyrin (PI-PII) and Porphyrin-Diatomic molecule-Porphyrin (P1-AB-P11) (AB = NO, CO, and 02) complexes are performed using HF method. In order to understand the planarity and appropriate stacking size of porphyrins and also to infer the separation of diatomic molecules between porphyrin layers the behavior of PI-AB-PH complexes (where AB = NO, CO, and 02) are analyzed using structural properties and molecular electrostatic potentials (MEP). The MEPs are caiculated using hybrid exchange correlation functional B3PW91 of DFT Mong with 6-31+G basis set for the PI-PH and PI-AB-Pzz complexes obtained from HF method. 展开更多
关键词 PORPHYRIN ab initio density functional theory diatomic molecules molecular storage
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