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The Quantum Condition That Should Have Been Assumed by Bohr When Deriving the Energy Levels of a Hydrogen Atom 被引量:2
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作者 Koshun Suto 《Journal of Applied Mathematics and Physics》 2021年第6期1230-1244,共15页
Bohr assumed a quantum condition when deriving the energy levels of a hydrogen atom. This famous quantum condition was not derived logically, but it beautifully explained the energy levels of the hydrogen atom. Theref... Bohr assumed a quantum condition when deriving the energy levels of a hydrogen atom. This famous quantum condition was not derived logically, but it beautifully explained the energy levels of the hydrogen atom. Therefore, Bohr’s quantum condition was accepted by physicists. However, the energy levels predicted by the eventually completed quantum mechanics do not match perfectly with the predictions of Bohr. For this reason, it cannot be said that Bohr’s quantum condition is a perfectly correct assumption. Since the mass of an electron which moves inside a hydrogen atom varies, Bohr’s quantum condition must be revised. However, the newly derived relativistic quantum condition is too complex to be assumed at the beginning. The velocity of an electron in a hydrogen atom is known as the Bohr velocity. This velocity can be derived from the formula for energy levels derived by Bohr. The velocity <em>v </em>of an electron including the principal quantum number <em>n</em> is given by <em>αc</em>/<em>n</em>. This paper elucidates the fact that this formula is built into Bohr’s quantum condition. It is also concluded in this paper that it is precisely this velocity formula that is the quantum condition that should have been assumed in the first place by Bohr. From Bohr’s quantum condition, it is impossible to derive the relativistic energy levels of a hydrogen atom, but they can be derived from the new quantum condition. This paper proposes raising the status of the previously-known Bohr velocity formula. 展开更多
关键词 Relativistic Energy Levels of the hydrogen atom bohr’s Quantum Condition bohr Velocity Einstein’s Energy-Momentum Relationship Suto’s Energy-Momentum Relationship Relativistic Kinetic Energy
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Catalytic activity of V_(2)CO_(2) MXene supported transition metal single atoms for oxygen reduction and hydrogen oxidation reactions:A density functional theory calculation study
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作者 Zhongjing Deng Xingqun Zheng +3 位作者 Mingming Deng Li Li Li Jing Zidong Wei 《Chinese Journal of Catalysis》 SCIE EI CAS CSCD 2021年第10期1659-1666,共8页
Two-dimensional(2D)MXene and single-atom(SA)catalysts are two frontier research fields in catalysis.2D materials with unique geometric and electronic structures can modulate the catalytic performance of supported SAs,... Two-dimensional(2D)MXene and single-atom(SA)catalysts are two frontier research fields in catalysis.2D materials with unique geometric and electronic structures can modulate the catalytic performance of supported SAs,which,in turn,affect the intrinsic activity of 2D materials.Density functional theory calculations were used to systematically explore the potential of O-terminated V2C MXene(V_(2)CO_(2))-supported transition metal(TM)SAs,including a series of 3d,4d,and 5d metals,as oxygen reduction reaction(ORR)and hydrogen oxidation reaction(HOR)catalysts.The combination of TM SAs and V_(2)CO_(2)changes their electronic structure and enriches the active sites,and consequently regulates the intermediate adsorption energy and catalytic activity for ORR and HOR.Among the investigated TM-V_(2)CO_(2)models,Sc-,Mn-,Rh-,and PtMCCh showed high ORR activity,while Sc-,Ti-,V-,Cr-,and Mn-V_(2)CO_(2)exhibited high HOR activity.Specifically,Mn-and Sc-V_(2)CO_(2)are expected to serve as highly efficient and cost-effective bifunctional catalysts for fuel cells because of their high catalytic activity and stability.This work provides theoretical guidance for the rational design of efficient ORR and HOR bifunctional catalysts. 展开更多
关键词 Single atoms catalyst MXenes Oxygen reduction reaction hydrogen oxidation reaction Density functional theory Fuel cells
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Relativistic Reduction of the Electron-Nucleus Force in Bohr’s Hydrogen Atom and the Time of Electron Transition between the Neighbouring Quantum Energy Levels
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作者 Stanisław Olszewski 《Journal of Modern Physics》 2020年第6期944-951,共8页
The aim of the paper is to get an insight into the time interval of electron emission done between two neighbouring energy levels of the hydrogen atom. To this purpose, in the first step, the formulae of the special r... The aim of the paper is to get an insight into the time interval of electron emission done between two neighbouring energy levels of the hydrogen atom. To this purpose, in the first step, the formulae of the special relativity are applied to demonstrate the conditions which can annihilate the electrostatic force acting between the nucleus and electron in the atom. This result is obtained when a suitable electron speed entering the Lorentz transformation is combined with the strength of the magnetic field acting normally to the electron orbit in the atom. In the next step, the Maxwell equation characterizing the electromotive force is applied to calculate the time interval connected with the change of the magnetic field necessary to produce the force. It is shown that the time interval obtained from the Maxwell equation, multiplied by the energy change of two neighbouring energy levels considered in the atom, does satisfy the Joule-Lenz formula associated with the quantum electron energy emission rate between the levels. 展开更多
关键词 hydrogen atom the bohr Model Lorentz Transformation Done with the Aid of the Electron Orbital Speed Maxwell Equation Applied to Calculate the Time Interval of Electron Transitions between Two Quantum Energy Levels Comparison with the Joule-Lenz Law for Energy Emission
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Zero Strength of the Lorentz Force and Lack of a Classical Energy Radiation in the Bohr's Hydrogen Atom?
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作者 Stanislaw Olszewski 《Journal of Modern Physics》 2019年第7期717-724,共8页
It is demonstrated that the Lorentz force acting on the electron particle in the Bohr's hydrogen atom, as well as the classical radiation energy of that atom, tends to be zero on condition both the electric and ma... It is demonstrated that the Lorentz force acting on the electron particle in the Bohr's hydrogen atom, as well as the classical radiation energy of that atom, tends to be zero on condition both the electric and magnetic fields in the atom are considered in a definite quantum state. The ratio of the mentioned fields becomes of importance for discussion of the occurence of the electron spin. 展开更多
关键词 bohr's hydrogen atom Lorentz Force CLASSICAL ELECTRON RADIATION ENERGY ELECTRON Spin
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Phase-Space Areas of the Body Motion in the Solar System Deduced from the Bohr-Sommerfeld Atomic Theory and Approximate Invariance of Their Ratios for the Pairs of Planets and Satellites
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作者 Stanislaw Olszewski Tadeusz Kwiatkowski 《Journal of Modern Physics》 2012年第9期1142-1151,共10页
Energy-time and momentum-position phase spaces defined by the electron orbits in the hydrogen-like atom exhibit special properties of equivalence. It is demonstrated that equivalence of the same kind can be obtained f... Energy-time and momentum-position phase spaces defined by the electron orbits in the hydrogen-like atom exhibit special properties of equivalence. It is demonstrated that equivalence of the same kind can be obtained for the phase-space areas defined by the orbit pairs of planets, or satellites, which compose the solar system. In the choice of the examined areas it is useful to be guided by the Bohr-Sommerfeld atomic theory. 展开更多
关键词 Ratios of the PHASE-SPACE Areas and theIR INVARIANCE Planets and SATELLITES bohr-Sommerfeld atomic theory
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Experimental and Theoretical Study of Hydrogen Atom Abstraction from C2H6 and C4H10 by Zirconium Oxide Clusters Anions 被引量:1
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作者 马嘉璧 吴晓楠 +2 位作者 赵艳霞 丁迅雷 何圣贵 《Chinese Journal of Chemical Physics》 SCIE CAS CSCD 2010年第2期133-137,I0001,共6页
The reactions of anionic zirconium oxide clusters ZrxOy- with C2H6 and C4H10 are investi-gated by a time of flight mass spectrometer coupled with a laser vaporization cluster source.Hydrogen containing products Zr2O5H... The reactions of anionic zirconium oxide clusters ZrxOy- with C2H6 and C4H10 are investi-gated by a time of flight mass spectrometer coupled with a laser vaporization cluster source.Hydrogen containing products Zr2O5H- and Zr3O7H- are observed after the reaction. Den-sity functional theory calculations indicate that the hydrogen abstraction is favorable in the reaction of Zr2O5- with C2H6, which supports that the observed Zr2O5H- and Zr3O7H- are due to hydrogen atom abstraction from the alkane molecules. This work shows a newpossible pathway in the reaction of zirconium oxide cluster anions with alkane molecules. 展开更多
关键词 Time of flight mass spectrometry Zirconium oxide cluster anion Reactivity Density functional theory hydrogen atom abstraction
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Bohr’s Spectrum of Quantum States in the Atomic Hydrogen Deduced from the Uncertainty Principle for Energy and Time
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作者 Stanislaw Olszewski 《Journal of Modern Physics》 2014年第14期1264-1271,共8页
A modified uncertainty principle coupling the intervals of energy and time can lead to the shortest distance attained in course of the excitation process, as well as the shortest possible time interval for that proces... A modified uncertainty principle coupling the intervals of energy and time can lead to the shortest distance attained in course of the excitation process, as well as the shortest possible time interval for that process. These lower bounds are much similar to the interval limits deduced on both the experimental and theoretical footing in the era when the Heisenberg uncertainty principle has been developed. In effect of the bounds existence, a maximal nuclear charge Ze acceptable for the Bohr atomic ion could be calculated. In the next step the velocity of electron transitions between the Bohr orbits is found to be close to the speed of light. This result provides us with the energy spectrum of transitions similar to that obtained in the Bohr’s model. A momentary force acting on the electrons in course of their transitions is estimated to be by many orders larger than a steady electrostatic force existent between the atomic electron and the nucleus. 展开更多
关键词 Uncertainty Principle for Energy and Time bohr’s Spectrum of Quantum levels in the hydrogen atom
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Emission Intensity in the Hydrogen Atom Calculated from a Non-Probabilistic Approach to the Electron Transitions 被引量:3
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作者 Stanisƚaw Olszewski 《Journal of Modern Physics》 2016年第8期827-851,共25页
Quantum aspects of the Joule-Lenz law for the transmission of energy allowed us to calculate the time rate of energy transitions between the quantum states of the hydrogen atom in a fully non-probabilistic way. The ca... Quantum aspects of the Joule-Lenz law for the transmission of energy allowed us to calculate the time rate of energy transitions between the quantum states of the hydrogen atom in a fully non-probabilistic way. The calculation has been extended to all transitions between p and s states having main quantum numbers not exceeding 6. An evident similarity between the intensity pattern obtained from the Joule-Lenz law and the corresponding quantum-mechanical transition pro-babilities has been shown. 展开更多
关键词 Time Intervals for the Electron Transitions in the hydrogen atom Non-Probabilistic theory of Energy Emission in the atom Comparison of the Emission Intensities with the Quantum-Mechanical Transition Probabilities
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Two Problems of Time Entering Respectively the Relativistic Mechanics and Electron Transport in Quantum Theory
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作者 Stanisław Olszewski 《World Journal of Mechanics》 2020年第10期186-197,共12页
In the relativistic mechanics, we calculate a minimal distance between the time scale of a one-dimensional motion having a larger velocity and the time scale of a similar motion with a lower velocity. Concerning the q... In the relativistic mechanics, we calculate a minimal distance between the time scale of a one-dimensional motion having a larger velocity and the time scale of a similar motion with a lower velocity. Concerning the quantum theory, we demonstrate that mechanical parameters entering the electron motion in the Bohr hydrogen atom can provide us with a correct size of the time interval entering the Joule-Lenz law for the emission energy between two neighbouring quantum levels of the atom. 展开更多
关键词 Time in the Special Relativity theory Time in the Quantum theory of the bohr atom Joule-Lenz Law for the Emission of Energy in the atom
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Model of the Pulsing Atom
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作者 Heinrich Ehrlich 《Advances in Materials Physics and Chemistry》 2017年第5期188-197,共10页
In this work, we reanalyzed the movement of an electron in the electrostatic field of nucleus. The trajectory of the electron’s motion is an ellipse with a minor semiaxis, tending towards zero. From a mathematical po... In this work, we reanalyzed the movement of an electron in the electrostatic field of nucleus. The trajectory of the electron’s motion is an ellipse with a minor semiaxis, tending towards zero. From a mathematical point of view the movement of an electron in such an orbit will be equivalent to the oscillation of an electron. The action produced by electrons in movement between stationary points is discrete and proportional to a Planck constant. This condition sets the allowable values of the electron energy and the radius of their orbit. Electrons on the same shell perform symmetric synchronous oscillations. Their frequency is of the order of 1016 Hz. Most of the time the electrons are located on the periphery of the atom, periodically they simultaneously rush to the nucleus, the atom rapidly compresses and immediately decompresses, i.e. pulsates. The model gives Bohr formula for the energy of single-electron atom and suitable values of ionization potentials of the atoms of the second period of the Periodic Table. 展开更多
关键词 atom Structure QUANTUM theory OSCILLATION bohr-Sommerfeld Model IONIZATION POTENTIALS
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Relativistic Correction of the Rydberg Formula 被引量:1
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作者 Koshun Suto 《Journal of Modern Physics》 2020年第2期294-303,共10页
The relationship E = &minus;K holds between the energy E and kinetic energy K of the electron constituting a hydrogen atom. If the kinetic energy of the electron is determined based on that relationship, then the ... The relationship E = &minus;K holds between the energy E and kinetic energy K of the electron constituting a hydrogen atom. If the kinetic energy of the electron is determined based on that relationship, then the energy levels of the hydrogen atom are also determined. In classical quantum theory, there is a formula called the Rydberg formula for calculating the wavelength of a photon emitted by an electron. In this paper, in contrast, the formula for the wavelength of a photon is derived from the relativistic energy levels of a hydrogen atom derived by the author. The results show that, although the Rydberg constant is classically a physical constant, it cannot be regarded as a fundamental physical constant if the theory of relativity is taken into account. 展开更多
关键词 RYDBERG FORMULA RYDBERG Constant CLASSICAL Quantum theory ENERGY-MOMENTUM Relationship in a hydrogen atom RELATIVISTIC Kinetic Energy
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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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Relativized Quantum Physics Generating <i>N</i>-Valued Coulomb Force and Atomic Hydrogen Energy Spectrum
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作者 Walter J. Christensen Jr. 《Journal of Modern Physics》 2015年第3期194-200,共7页
Though not well-known, Einstein endeavored much of his life to general-relativize quantum mechanics, (rather than quantizing gravity). Albeit he did not succeed, his legacy lives on. In this paper, we begin with the g... Though not well-known, Einstein endeavored much of his life to general-relativize quantum mechanics, (rather than quantizing gravity). Albeit he did not succeed, his legacy lives on. In this paper, we begin with the general relativistic field equations describing flat spacetime, but stimulated by vacuum energy fluctuations. In our precursor paper, after straightforward general relativistic calculations, the resulting covariant and contravariant energy-momentum tensors were identified as n-valued operators describing graviton excitation. From these two operators, we were able to generate all three boson masses (including the Higgs mass) in precise agreement as reported in the 2010 CODATA (NIST);moreover local, as-well-as large-scale, accelerated spacetimes were shown to naturally occur from this general relativized quantum physics approach (RQP). In this paper, applying the same approach, we produce an n-valued Coulombs Force Law leading to the energy spectrum for atomic hydrogen, without assuming quantized atomic radii, velocity and momentum, as Bohr did. 展开更多
关键词 GENERAL Relativity GENERAL Relativizing Quantum Mechanics Fundamental Constants Coulombs Force Law atomic hydrogen Energy States bohr Radius Higgs MASS BOSONS MASS Hierarchy Rydberg Constant Hawking Radiation
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Investigation of the Antioxidant and UV Absorption Properties of 2-(2’-hydroxy-5’-methylphenyl)-benzotriazole and Its Ortho-Substituted Derivatives via DFT/TD-DFT
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作者 Numbonui Stanley Tasheh Aymard Didier Tamafo Fouegue Julius Numbonui Ghogomu 《Computational Chemistry》 2021年第3期161-196,共36页
The demand and pursuit of chemical entities with UV filtration and antioxidant properties for enhanced photoprotection have been driven in recent times by acute exposure of humans to solar ultraviolet radiations. The ... The demand and pursuit of chemical entities with UV filtration and antioxidant properties for enhanced photoprotection have been driven in recent times by acute exposure of humans to solar ultraviolet radiations. The structural, electronic, antioxidant and UV absorption properties of drometrizole (PBT) and designed ortho-substituted derivatives are reported via DFT and TD-DFT in the gas and aqueous phases. DFT and TD-DFT computations were performed at the M062x-D3Zero/6-311++G(d,p)//B97-3c and PBE0-D3(BJ)/def2-TZVP levels of theory respectively. Reaction enthalpies related to hydrogen atom transfer (HAT), single-electron transfer followed by proton transfer (SET-PT), and sequential proton loss electron transfer (SPLET) mechanisms were computed and compared with those of phenol. Results show that the presence of -NH2 substituent reduces the O-H bond dissociation enthalpy and ionization potential, while that of -CN increases the proton affinity. The HAT and SPLET mechanisms are the most plausible in the gas and aqueous phases respectively. The molecule with the -NH2 substituent (PBT1) was identified to be the compound with the highest antioxidant activity. The UV spectra of the studied compounds are characterized by two bands in the 280 - 400 nm regions. Results from this study provide a better comprehension antioxidant mechanism of drometrizole and present a new perspective for the design of electron-donor antioxidant molecules with enhanced antioxidant-photoprotective efficiencies for applications in commercial sunscreens. 展开更多
关键词 ANTIOXIDANT Drometrizole Density Functional theory Ultraviolet Absorption hydrogen atom Transfer Single Electron-Proton Transfer and Sequential Proton Loss Electron Transfer Mechanisms
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The dynamical properties of Rydberg hydrogen atom near a metal surface 被引量:2
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作者 GE Meihua1, ZHANG Yanhui1, WANG Dehua2, DU Mengli3 & LIN Shenglu1 1. College of Physics and Electronics, Shandong Normal University, Jinan 250014, China 2. Department of Mathematics and Physics, Shandong Institute of Architecture and Engineering, Jinan 250014, China 3. Institute of Theoretical Physics, Chinese Academy of Sciences, Beijing 100080, China 《Science China(Physics,Mechanics & Astronomy)》 SCIE EI CAS 2005年第6期667-675,共9页
The dynamical properties of Rydberg hydrogen atom near a metal surface are presented by using the methods of phase space analysis and closed orbit theory. Transforming the coordinates of the Hamiltonian, we find that ... The dynamical properties of Rydberg hydrogen atom near a metal surface are presented by using the methods of phase space analysis and closed orbit theory. Transforming the coordinates of the Hamiltonian, we find that the phase space of the system is divided into vibrational and rotational region. Both the Poincaré surface of section and the closed orbit theory verify the same conclusion clearly. In this paper we choose the atomic principal quantum number as n = 20. The dynamical character of the exited hydrogen atom depends sensitively on the atom-surface distance d. When d is sufficiently large, the atom-surface potential can be expressed by the traditional van der Waals force and the system is integrable. When d becomes smaller, there exists a critical value dc. For d > dc, the system is near-integrable and the motion is regular. While chaotic motion appears for d < dc, and the system tends to be non-integrable. The trajectories become unstable and the electron might be captured onto the metal surface. 展开更多
关键词 RYDBERG hydrogen atom VAN der WAALS interaction POINCARÉ surface of section closed orbit theory chaos.
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A Mechanistic Switch in C-H Bond Activation by Elusive Fe^(V)(O)(TAML)Reaction Intermediate:A Theoretical Study 被引量:1
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作者 Anran Zhou Zhiqiang Fu +2 位作者 Xuanyu Cao Yufen Zhao Yong Wang 《Chinese Journal of Chemical Physics》 SCIE EI CAS CSCD 2022年第2期383-389,I0032-I0064,I0004,共41页
The divergent behavior of C-H bond oxidations of aliphatic substrates compared to those of aromatic substrates shown in Gupta’s experiment was mechanistically studied herein by means of density functional theory calc... The divergent behavior of C-H bond oxidations of aliphatic substrates compared to those of aromatic substrates shown in Gupta’s experiment was mechanistically studied herein by means of density functional theory calculations.Our calculations reveal that such difference is caused by different reaction mechanisms between two kinds of substrates(the aliphatic cyclohexane,2,3-dimethylbutane and the aromatic toluene,ethylbenzene and cumene).For the aliphatic substrates,C-H oxidation by the oxidant Fe^(V)(O)(TAML)is a hydrogen atom transfer process;whereas for the aromatic substrates,C-H oxidation is a proton-coupled electron transfer(PCET)process with a proton transfer character on the transition state,that is,a proton-coupled electron transfer process holding a proton transfer-like transition state(PCET(PT)).This difference is caused by the strongπ-πinteractions between the tetra-anionic TAML ring and the phenyl ring of the aromatic substrates,which has a“pull”effect to make the electron transfer from substrates to the Fe=O moiety inefficient. 展开更多
关键词 C-H bond activation hydrogen atom transfer Proton coupled electron transfer Density functional theory
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Quantum Mechanics of Moving Bound States 被引量:1
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作者 Y. S. Kim 《Journal of Modern Physics》 2022年第2期138-165,共28页
The quantum mechanics of bound states with discrete energy levels is well understood. The quantum mechanics of scattering processes is also well understood. However, the quantum mechanics of moving bound states is sti... The quantum mechanics of bound states with discrete energy levels is well understood. The quantum mechanics of scattering processes is also well understood. However, the quantum mechanics of moving bound states is still debatable. When it is at rest, the space-like separation between the constituent particles is the primary variable. When the bound state moves, this space-like separation picks up the time-like separation. The time-separation is not a measurable variable in the present form of quantum mechanics. The only way to deal with this un-observable variable is to treat it statistically. This leads to rise of the statistical variables such entropy and temperature. Paul A. M. Dirac made efforts to construct bound-state wave functions in Einstein’s Lorentz-covariant world. In 1927, he noted that the c-number time-energy relation should be incorporated in the relativistic world. In 1945, he constructed four-dimensional oscillator wave functions with one time coordinate in addition to the three-dimensional space. In 1949, Dirac introduced the light-cone coordinate system for Lorentz transformations. It is then possible to integrate these contributions made by Dirac to construct the Lorentz-covariant harmonic oscillator wave functions. This oscillator system can explain the proton as a bound state of the quarks when it is at rest, and explain the Feynman’s parton picture when it moves with a speed close to that of light. While the un-measurable time-like separation becomes equal to the space-like separation at this speed, the statistical variables become prominent. The entropy and the temperature of this covariant harmonic oscillator are calculated. It is shown that they rise rapidly as the proton speed approaches that of light. 展开更多
关键词 Bound States in Einstein’s World bohr and Einstein on the hydrogen atom Quark-Parton Puzzle Lorentz Group
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Theoretical Investigation on Interaction between Guanine and Luteolin
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作者 Lai-cai Li Kun-kun Bai Wan-fei Cai 《Chinese Journal of Chemical Physics》 SCIE CAS CSCD 2013年第5期533-540,I0003,共9页
The interacting patterns of the luteolin and guanine have been investigated by using the density functional theory B3LYP method with 6-31+G* basis set. Eighteen stable structures for the luteolin-guanine complexes h... The interacting patterns of the luteolin and guanine have been investigated by using the density functional theory B3LYP method with 6-31+G* basis set. Eighteen stable structures for the luteolin-guanine complexes have been found respectively. The results indicate that the complexes are mainly stabilized by the hydrogen bonding interactions. Meanwhile, both the number and strength of hydrogen bond play important roles in determining the stability of the complexes which can form two or more hydrogen bonds. Theories of atoms in molecules and natural bond orbital have also been utilized to investigate the hydrogen bonds involved in all the systems. The interaction energies of all the complexes which were corrected by basis set superposition error are 6.04-56.94 kJ/mol. The calculation results indicate that there are strong hydrogen bonding interactions in the luteolin-guanine complexes. We compared the interaction between luteolin and four bases of DNA, and found luteolin-thymine was the strongest and luteolin-adenine was the weakest. The interaction between luteolin and DNA bases are all stronger than luteolin-water. 展开更多
关键词 Density functional theory LUTEOLIN GUANINE hydrogen bond atoms inmolecules Natural bond orbital
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Theoretical Study on the Hydrogen Bonding Interactions in Complexes of 5-Hydroxytryptamine with Water
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作者 Lingfei Guo Zhengguo Huang +2 位作者 Tingting Shen Lingling Ma Xiqian Niu 《Chinese Journal of Chemistry》 SCIE CAS CSCD 2013年第8期1079-1086,共8页
The energies, geometries and harmonic vibrational frequencies of 1 : 1 5-hydroxytryptamine-water (5-HT-H20) complexes are studied at the MP2/6-311 + + G(d,p) level. Natural bond orbital (NBO), quantum theory ... The energies, geometries and harmonic vibrational frequencies of 1 : 1 5-hydroxytryptamine-water (5-HT-H20) complexes are studied at the MP2/6-311 + + G(d,p) level. Natural bond orbital (NBO), quantum theory of atoms in molecules (QTAIM) analyses and the localized molecular orbital energy decomposition analysis (LMO-EDA) were performed to explore the nature of the hydrogen-bonding interactions in these complexes. Various types of hydro- gen bonds (H-bonds) are formed in these 5-HT-H20 complexes. The intermolecular C4H55HT'"Ow H-bond in HTW3 is strengthened due to the cooperativity, whereas no such cooperativity is found in the other 5-HT-H20 complexes. H-bond in which nitrogen atom of amino in 5-HT acted as proton donors was stronger than other H-bonds. Our researches show that the hydrogen bonding interaction plays a vital role on the relative stabilities of 5-HT-H20 complexes. 展开更多
关键词 natural bond orbital (NBO) quantum theory of atoms in molecules (QTAIM) localized molecular or-bital energy decomposition analysis (LMO-EDA) hydrogen bond
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氢原子低能级的Stark效应 被引量:15
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作者 许新胜 张先燚 涂兴华 《安徽师范大学学报(自然科学版)》 CAS 2001年第1期21-26,共6页
用微扰法计算了氢原子低能级的Stark效应 ,基态精确到二级修正 ,能级产生移动 ;第一激发态、第二激发态精确到一级修正 ,能级产生分裂 ,简并部分解除 .
关键词 能级 STARK效应 激发态 氢原子 二级修正 简并 氩原子 微扰法 移动 分解
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