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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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Time Intervals of the Electron Transitions between the Energy States in the Hydrogen Atom Calculated in a Non-Probabilistic Way 被引量:1
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作者 Stanislaw Olszewski 《Journal of Modern Physics》 2019年第13期1522-1531,共10页
Definitions of the mechanical parameters entering the Bohr model of the hydrogen atom allowed us to calculate the time intervals connected with the electron transitions between the nearest-neighbouring energy levels i... Definitions of the mechanical parameters entering the Bohr model of the hydrogen atom allowed us to calculate the time intervals connected with the electron transitions between the nearest-neighbouring energy levels in the atom. This is done in a strictly non-probabilistic way. The time results are compared with those derived earlier on the basis of the classical Joule-Lenz law for the energy emission adapted to the case of the electron transfer in the quantum systems. A similar formalism has been next applied to the harmonic oscillator and a particle moving in the one-dimensional potential box. 展开更多
关键词 Spectrum of the Hydrogen Atom Time Intervals of the electron transitions
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ABSORPTION SPECTRA OF 4f ELECTRON TRANSITIONS IN THE SYSTEM OF NEODYMIUMSEMIXYLENOL ORANGE-CETYLPYRIDINIUM CHLORIDE
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作者 Nai Xing Wang Department of Chemistry, Shandong University, Jinan, 250100 《Chinese Chemical Letters》 SCIE CAS CSCD 1991年第5期381-382,共2页
In this paper the absorption spectra of Nd-SXO-CPC complex by 4f electron transitions have been studied by zero-order and fourth-order derivative spectrophotome-try. The molar absorptivity is 2.6×10~3 1.mol^(-1).... In this paper the absorption spectra of Nd-SXO-CPC complex by 4f electron transitions have been studied by zero-order and fourth-order derivative spectrophotome-try. The molar absorptivity is 2.6×10~3 1.mol^(-1).cm^(-1) at 585 nm, the fourth-order derivative molar absorptivity is 1.4×10~4 1.mol^(-1).cm^(-1) at 584.5(-) and 587(+) nm. They are 300 times and 1600 times greater than those of the chloride, respectively. 展开更多
关键词 ND THAN ABSORPTION SPECTRA OF 4f electron transitions IN THE SYSTEM OF NEODYMIUMSEMIXYLENOL ORANGE-CETYLPYRIDINIUM CHLORIDE
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Quanta of the Phase-Space Areas Given by Intervals of Energy and Time Associated with Electron Transitions
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作者 Stanislaw Olszewski 《Journal of Modern Physics》 2017年第8期1158-1174,共17页
The paper examines the energy of electron transitions in an emission process and the time intervals necessary for that process. For simple quantum systems, the both parameters—that of energy and time—depend on the d... The paper examines the energy of electron transitions in an emission process and the time intervals necessary for that process. For simple quantum systems, the both parameters—that of energy and time—depend on the difference &Delta;n of the quantum numbers n labelling the beginning and end state of emission. It is shown that the phase-space areas formed by products of energy and time involved in the emission can be represented as a quadratic function of &Delta;n multiplied by the Planck constant h. 展开更多
关键词 electron transitions Their Energies and Transition Times Quanta of the Phase-Space Areas of Energy and Time
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Joule-Lenz Energy of Quantum Electron Transitions Compared with the Electromagnetic Emission of Energy
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作者 Stanisław Olszewski 《Journal of Modern Physics》 2016年第12期1440-1448,共10页
In the first step, the Joule-Lenz dissipation energy specified for the electron transitions between two neighbouring quantum levels in the hydrogen atom has been compared with the electromagnetic energy of emission fr... In the first step, the Joule-Lenz dissipation energy specified for the electron transitions between two neighbouring quantum levels in the hydrogen atom has been compared with the electromagnetic energy of emission from a single level. Both the electric and magnetic vectors entering the Pointing vector of the electromagnetic field are referred to the one-electron motion performed along an orbit in the atom. In the next step, a similar comparison of emission rates is performed for the harmonic oscillator. Formally a full agreement of the Joule-Lenz and electromagnetic expressions for the energy emission rates has been attained. 展开更多
关键词 Joule-Lenz Energy Quantum electron transitions Hydrogen Atom Electromagnetic Energy Emission
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Scheme for the excitation of thorium-229 nuclei based on electronic bridge excitation 被引量:1
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作者 Lin Li Zi Li +3 位作者 Chen Wang Wen‑Ting Gan Xia Hua Xin Tong 《Nuclear Science and Techniques》 SCIE EI CAS CSCD 2023年第2期88-97,共10页
Thorium-229 possesses the lowest first nuclear excited state,with an energy of approximately 8 eV.The extremely narrow linewidth of the first nuclear excited state,with an uncertainty of 53 THz,prevents direct laser e... Thorium-229 possesses the lowest first nuclear excited state,with an energy of approximately 8 eV.The extremely narrow linewidth of the first nuclear excited state,with an uncertainty of 53 THz,prevents direct laser excitation and realization of the nuclear clock.We present a proposal using the Coulomb crystal of a linear chain formed by229Th^(3+)ions,where the nuclei of229Th3+ions in the ion trap are excited by the electronic bridge(EB)process.The 7 P1∕2state of the thorium-229 nuclear ground state is chosen for EB excitation.Using the two-level optical Bloch equation under experimental conditions,we calculate that 2 out of 36 prepared thorium ions in the Coulomb crystal can be excited to the first nuclear excited state,and it takes approximately 2 h to scan over an uncertainty of 0.22 eV.Taking advantage of the transition enhancement of EB and the long stability of the Coulomb crystal,the energy uncertainty of the first excited state can be limited to the order of 1 GHz. 展开更多
关键词 Coulomb crystal Thorium-229 electronic bridge transition Isomeric state
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Unveiling the pressure-driven metal–semiconductor–metal transition in the doped TiS_(2)
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作者 陈佳骏 吕心邓 +3 位作者 李思敏 但雅倩 黄艳萍 崔田 《Chinese Physics B》 SCIE EI CAS CSCD 2024年第6期63-67,共5页
Conventional theories expect that materials under pressure exhibit expanded valence and conduction bands,leading to increased electrical conductivity.Here,we report the electrical properties of the doped 1T-TiS_(2) un... Conventional theories expect that materials under pressure exhibit expanded valence and conduction bands,leading to increased electrical conductivity.Here,we report the electrical properties of the doped 1T-TiS_(2) under high pressure by electrical resistance investigations,synchrotron x-ray diffraction,Raman scattering and theoretical calculations.Up to 70 GPa,an unusual metal-semiconductor-metal transition occurs.Our first-principles calculations suggest that the observed anti-Wilson transition from metal to semiconductor at 17 GPa is due to the electron localization induced by the intercalated Ti atoms.This electron localization is attributed to the strengthened coupling between the doped Ti atoms and S atoms,and the Anderson localization arising from the disordered intercalation.At pressures exceeding 30.5 GPa,the doped TiS_(2) undergoes a re-metallization transition initiated by a crystal structure phase transition.We assign the most probable space group as P2_12_12_1.Our findings suggest that materials probably will eventually undergo the Wilson transition when subjected to sufficient pressure. 展开更多
关键词 high pressure transition metal dichalcogenides doped TiS_(2) electronic phase transition
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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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Electron Transition of Eu^(2+) and Energy Transfer in Crystals BaFX:Eu^(2+),Eu^(3+) (X=Cl,Br) 被引量:1
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作者 赵纬 宋增福 苏勉曾 《Journal of Rare Earths》 SCIE EI CAS CSCD 1992年第4期241-246,共6页
In crystals BaFX:Eu^(2+)(X=Cl,Br).there exists configuration interaction between 4f^65d and 4f^65s ex- cited state of Eu^(2+)ion.and it results in the change of relative intensities of d-f and f-f transition.The trans... In crystals BaFX:Eu^(2+)(X=Cl,Br).there exists configuration interaction between 4f^65d and 4f^65s ex- cited state of Eu^(2+)ion.and it results in the change of relative intensities of d-f and f-f transition.The transition ~S_-_2→4f^65d-6s is observed.The variation of F/X atomic ratio between 110/90 and 90/110 does not obvi- ously influence the luminescence of BaFX:Eu^(2-).There is energy transfer between Eu^(2+)(f-f)and Eu^(3+)which coexists in the matrices. 展开更多
关键词 Barium fluorohalide Europium ions electron transition Energy transfer
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Effect and Mechanism Analysis of Solvent on the Electron Transition of Fluoroquinolones Based on Quantum Chemical Calculation 被引量:1
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作者 陈凤先 海热提 《Chinese Journal of Structural Chemistry》 SCIE CAS CSCD 2017年第12期1931-1946,共16页
Ciprofloxacin(CIP), moxifoxacin(MOX) and enrofloxacin(ENR) were selected as typical fluoroquinolones(FQs) to analyze the excitation-enhancing effect and mechanism of solvents on FQs' electron transition based... Ciprofloxacin(CIP), moxifoxacin(MOX) and enrofloxacin(ENR) were selected as typical fluoroquinolones(FQs) to analyze the excitation-enhancing effect and mechanism of solvents on FQs' electron transition based on quantum chemical calculations. The UV spectra of three FQs in gas and five different solvents(water, cyclohexane, dimethylsulfoxide, methanol, acetone) were calculated using Gaussian 09 software. The transition mechanisms of FQs' main electron transitions were analyzed by natural bond orbital(NBO) theory, and the solvent effect on each electron transition was assessed qualitatively and quantitatively by sensitivity analysis and an established index system. The excitation enhancing mechanism of solvent on electron transitions of FQs was analyzed from the view of photo-induced reactions between solvent and FQs molecules. The results show that there are two main transitions located in the spectrum ranges of 300~380 and 240~300 nm for each FQ in any medium, which are assigned as n →π* and π→π* electron transitions, respectively. By comparison, the n →π* transition is more sensitive to solvent because of the energy transfer between solvent molecules and FQs, but the solvent effect on the π→π* transition is stronger than on the n →π* transition. The sequence of affected extent of solvent effect on electron transition was CIP 〉 MOX 〉 ENR, and the sequence of solvent effect was water 〉 DMSO 〉 methanol 〉 acetone 〉 cyclohexane(stronger solvent effect with increasing the dielectric constant of solvent). From the view of photo-induced reactions, the reaction between FQs*T1 and solvent*T1 has the decisive regulatory effect on the n →π* transition of FQs in solvent, and the reaction between FQsS0 and solvent*TI has an enhancing effect on the π→π* transition. 展开更多
关键词 FLUOROQUINOLONES electron transition solvent effect index system photo-induced reaction
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Giant Volume Magnetostriction Caused by Itinerant Electron Metamagnetic Transition and Pronounced Invar Effects in La(Fe_xSi_(1-x))_(13) Compounds 被引量:1
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作者 K.Fukamichi and A.Fujita (Department of Materials Science, Graduate School of Engineering, Tohoku University, Aoba-yama 02, Sendai 980-8579, Japan) 《Journal of Materials Science & Technology》 SCIE EI CAS CSCD 2000年第2期167-171,共5页
A first-order itinerant electron metamagnetic (IEM) transition above the Curie temperature Tc for ferromagnetic La(Fe_xSi_1-x)13 compounds has been confirmed by applying magnetic field. The volume change just above T_... A first-order itinerant electron metamagnetic (IEM) transition above the Curie temperature Tc for ferromagnetic La(Fe_xSi_1-x)13 compounds has been confirmed by applying magnetic field. The volume change just above T_C for x=0.88 is huge of about 1.5%, which is caused by a large magnetic moment induced by the IEM transition. These compounds have a possibility for practical applications as giant magnetostrictive materials. Pronounced Invar effects bring about a negative thermal expansion below TC, closely correlated with the negative mode-mode coupling among spin fluctuations. 展开更多
关键词 COMPOUNDS Fe_xSi Giant Volume Magnetostriction Caused by Itinerant electron Metamagnetic Transition and Pronounced Invar Effects in La
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A Precise Description of the Electronic Structures and Spin-Allowed Transition Properties of PF and Its Cation:All-Electron Configuration-Interaction Investigations Including Relativistic Effect 被引量:1
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作者 李奇楠 赵书涛 +3 位作者 张晓美 罗旺 李瑞 闫冰 《Chinese Physics Letters》 SCIE CAS CSCD 2015年第7期42-46,共5页
The electronic structures of PF and PF+ are calculated with the high-level configuration interaction method. To improve the precision of calculations, the spin-orbit coupling effect, the scalar relativistic effect, a... The electronic structures of PF and PF+ are calculated with the high-level configuration interaction method. To improve the precision of calculations, the spin-orbit coupling effect, the scalar relativistic effect, and the Davidson correction(q-Q) are also considered. The spectroscopic parameters of bound states are derived by the electronic structures of PF and PF+, which are in good accordance with the measurements. The transition dipole moments of spin-allowed transitions are evaluated, and the radiative lifetimes of several A S states of PF and PF+ are obtained. 展开更多
关键词 A Precise Description of the electronic Structures and Spin-Allowed Transition Properties of PF and Its Cation:All-electron Configuration-Interaction Investigations Including Relativistic Effect PF TDM
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Microwave awakening the n-π^(*) electronic transition in highly crystalline polymeric carbon nitride nanosheets for photocatalytic hydrogen generation
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作者 Xiangang Lin Haiwei Du +4 位作者 Daochuan Jiang Peng Zhang Zhiwu Yu Hong Bi Yupeng Yuan 《Journal of Energy Chemistry》 SCIE EI CAS CSCD 2022年第2期541-547,共7页
The n-π^(*) electronic transition in polymeric carbon nitride(PCN)can remarkably harvest visible light,which thus potentially promotes the photocatalytic hydrogen H2 generation.However,awaking the n-π^(*) lectronic ... The n-π^(*) electronic transition in polymeric carbon nitride(PCN)can remarkably harvest visible light,which thus potentially promotes the photocatalytic hydrogen H2 generation.However,awaking the n-π^(*) lectronic transition has proven to be a grand challenge.Herein,we reported on the awakening of n-π^(*) electronic transition by microwave thermolysis of urea pellet,which yielded the PCN with absorption edge of 600 nm,near 140 nm red-shift from 460 nm of pristine PCN.The n-π^(*) electronic transition endows PCN with an increased photocata lytic H_(2) generation,with a highest H_(2) rate of 61.7μmol h^(-1) under visible light exposure,which is near 6 times higher than that by using the PCN from the thermolysis of urea pellets in an electric furnace(10.6μmol h^(-1)).Furthermore,the n-π^(*) transition in PCN leads to the longest wavelength of 535 nm that can initiate H2 generation,remarkably longer than the absorption edge of pristine PCN(460 nm).This work manifests the advantages of microwave sintering route to awaken the n-π^(*) electronic transition in PCN for an increased photocata lytic performance. 展开更多
关键词 Polymeric carbon nitride MICROWAVE n-π^(*)electronic transition Hydrogen
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THE LINEAR CORRELATIONS BETWEEN ELECTRONIC TRANSITION ENERGY AND HAMMETT CONSTANTS FOR THE SUBSTITUTED PORPHYRIN-LIKE MACROCYCLE
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作者 Shi Ming DONG Duo Yuan WANG Institute of Photographic Chemistry,Academia Sinica,Beijing 100101 《Chinese Chemical Letters》 SCIE CAS CSCD 1993年第3期243-246,共4页
The properties of absorption spectra are presented and the linear correlations of Hammett constants with the 0-0 transition energy(E_(o,o))of S_←S_o, and the ratios of oscillator strength(f/f)are used to probe the in... The properties of absorption spectra are presented and the linear correlations of Hammett constants with the 0-0 transition energy(E_(o,o))of S_←S_o, and the ratios of oscillator strength(f/f)are used to probe the interactions betwee π-electron of aromatic maerocycles or metal ion of complexes with the sub- stituents on β-position of benzene ring for porphyrin-like maerocyclic compounds. 展开更多
关键词 TXP Cd CI THE LINEAR CORRELATIONS BETWEEN electronIC TRANSITION ENERGY AND HAMMETT CONSTANTS FOR THE SUBSTITUTED PORPHYRIN-LIKE MACROCYCLE
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Electronic Structure Reconstruction across the Antiferromagnetic Transition in TaFe1.23Te3 Spin Ladder
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作者 徐敏 王莉敏 +19 位作者 彭瑞 葛青亲 陈飞 叶子荣 张焱 陈苏迪 夏淼 刘荣华 Arita M. Shimada K. Namatame H. Taniguchi M. Matsunami M. Kimura S. 史明 陈仙辉 尹卫国 顾威 谢斌平 封东来 《Chinese Physics Letters》 SCIE CAS CSCD 2015年第2期127-130,共4页
Employing the angle-resolved photoemission spectroscopy, we study the electronic structure of TaFe1.23Te3, a two-leg spin ladder compound with a novel antiferromagnetic ground state. Quasi-two-dimensional (2D) Fermi... Employing the angle-resolved photoemission spectroscopy, we study the electronic structure of TaFe1.23Te3, a two-leg spin ladder compound with a novel antiferromagnetic ground state. Quasi-two-dimensional (2D) Fermi surface is observed, with sizable inter-ladder hopping. Moreover, instead of observing an energy gap at the Fermi surface in the antiferromagnetic state, we observe the shifts of various bands. Combining these observations with density-functional-theory calculations, we propose that the large scale reconstruction of the electronic structure, caused by the interactions between the coexisting itinerant electrons and local moments, is most likely the driving force of the magnetic transition. Thus TaFe1.23Te3 serves as a simpler platform that contains similar ingredients to the parent compounds of iron-based superconductors. 展开更多
关键词 TA der electronic Structure Reconstruction across the Antiferromagnetic Transition in TaFe AFM
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In situ electronic structural study of VO_2 thin film across the metal–insulator transition
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作者 伊明江.买买提 阿布都艾则孜.阿布来提 +3 位作者 吴蕊 王嘉鸥 钱海杰 奎热西.依布拉欣 《Chinese Physics B》 SCIE EI CAS CSCD 2013年第12期410-415,共6页
The in situ valence band photoemission spectrum (PES) and X-ray absorption spectrum (XAS) at V LⅡ-LⅢ edges of the VO2 thin film, which is prepared by pulsed laser deposition, are measured across the metal–insul... The in situ valence band photoemission spectrum (PES) and X-ray absorption spectrum (XAS) at V LⅡ-LⅢ edges of the VO2 thin film, which is prepared by pulsed laser deposition, are measured across the metal–insulator transition (MIT) temperature (TMIT=67 ℃). The spectra show evidence for changes in the electronic structure depending on temperature. Across the TMIT, pure V 3d characteristic d‖ and O 2p-V 3d hybridization characteristic πpd, σpd bands vary in binding energy position and density of state distributions. The XAS reveals a temperature-dependent reversible energy shift at the V LⅢ-edge. The PES and XAS results imply a synergetic energy position shift of occupied valence bands and unoccupied conduction band states across the phase transition. A joint inspection of the PES and XAS results shows that the MIT is not a one-step process, instead it is a process in which a semiconductor phase appears as an intermediate state. The final metallic phase from insulating state is reached through insulator–semiconductor, semiconductor–metal processes, and vice versa. The conventional MIT at around the TMIT=67 ℃ is actually a semiconductor–insulator transformation point. 展开更多
关键词 vanadium dioxide metal–insulator transition electronic structure photoemission spectroscopy
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Time Intervals of the Energy Emission in Quantum Systems Obtained from the Conservation Rule of the Electron Momentum
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作者 Stanisław Olszewski 《Journal of Modern Physics》 2021年第5期661-670,共10页
The paper presents a non-probabilistic approach to the time interval associated with the energy emission produced by the electron transition in a quantum system. The calculations were performed for the hydrogen atom a... The paper presents a non-probabilistic approach to the time interval associated with the energy emission produced by the electron transition in a quantum system. The calculations were performed for the hydrogen atom and the electron particle in a one-dimensional potential box. In both cases, the rule of conservation of the electron momentum has been applied. The results, limited to the time intervals of transitions between two neighbouring quantum energy levels, occur to be much similar to those obtained earlier with the aid of the Joule-Lenz energy emission theory. 展开更多
关键词 Non-Probabilistic Approach to the electron Transition Time Conservation Rule of the electron Momentum Joule-Lenz Energy Emission Theory
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Structural Phase Transition and a Mutation of Electron Mobility in Zn_xCd_(1-x)O Alloys
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作者 张亚伟 杨凯科 邓惠雄 《Chinese Physics Letters》 SCIE CAS CSCD 2018年第5期87-90,共4页
We investigate the electronic structures and phase stability of ZnO, CdO and the related alloys in rocksalt(B1)and wurzite(B4) crystal, using the first-principle density functional theory within the hybrid functio... We investigate the electronic structures and phase stability of ZnO, CdO and the related alloys in rocksalt(B1)and wurzite(B4) crystal, using the first-principle density functional theory within the hybrid functional approximation. By varying the concentration of Zn components from 0% to 100%, we find that the Zn_xCd(1-x)O alloy undergoes a phase transition from octahedron to tetrahedron at x = 0.32, in agreement with the recent experimental findings. The phase transition leads to a mutation of the electron mobility originated from the changes of the effective mass. Our results qualify Zn O/Cd O alloy as an attractive candidate for photo-electrochemical and solar cell power applications. 展开更多
关键词 Structural Phase Transition and a Mutation of electron Mobility in Zn_xCd x)O Alloys ZN
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Fast-electron-impact study on excitations of 4d electron of xenon
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作者 张鑫 刘亚伟 +6 位作者 彭裔耕 徐龙泉 倪冬冬 康旭 王洋洋 祁月盈 朱林繁 《Chinese Physics B》 SCIE EI CAS CSCD 2015年第12期295-297,共3页
The electron energy loss spectrum of the 4d excitations of xenon was measured at an incident electron energy of1500 eV and a scattering angle of 6°. Besides the optically allowed transitions of 4d5/2^-1np and 4d3... The electron energy loss spectrum of the 4d excitations of xenon was measured at an incident electron energy of1500 eV and a scattering angle of 6°. Besides the optically allowed transitions of 4d5/2^-1np and 4d3/2^-1np, the optically forbidden transitions of 4d5/2^-1ns, 4d5/2^-1nd, 4d3/2^-1ns, and 4d3/2^-1nd were observed. The measured features are assigned with the help of the calculation by the Cowan Code. The line profile parameters of both optically allowed transitions and optically forbidden ones were determined and compared with the previous available data. It is found that the natural widths of both dipole-allowed and dipole-forbidden excitations are approximately identical, which means the spectator transitions dominate the resonant Auger effect for both dipole-allowed and dipole-forbidden transitions. 展开更多
关键词 electron energy loss spectrum optically forbidden transition natural width
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Electronic Structure and Visible-Light Absorption of Transition Metals(TM=Cr,Mn, Fe, Co) and Zn-Codoped SrTiO_3: a First-Principles Study
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作者 汪月琴 刘银 +1 位作者 张明旭 闵凡飞 《Chinese Physics Letters》 SCIE CAS CSCD 2018年第1期72-75,共4页
First-principles calculations are performed on the influence of transition metal(TM=Cr, Mn, Fe, Co) as codopants on the electronic structure and visible-light absorption of Zn-doped Sr TiO_3. The calculated results ... First-principles calculations are performed on the influence of transition metal(TM=Cr, Mn, Fe, Co) as codopants on the electronic structure and visible-light absorption of Zn-doped Sr TiO_3. The calculated results show that(Zn,Mn)-codoped Sr TiO_3 requires the smallest formation energy in four codoping systems. The structures of the codoped systems display obvious lattice distortion, inducing a phase transition from cubic to rhombohedral after codoping. Some impurity Cr, Mn and Co 3d states appear below the bottom of conduction band and some Fe 3d states are located above the top of valence band, which leads to a significant narrowing of band gap after transition metal codoping. The enhancement of visible-light absorption are observed in transition metals(TM=Cr, Mn, Fe, Co) and Zn codoped Sr TiO_3 systems. The prediction calculations suggested that the(Zn,Mn)-and(Zn,Co)-codoped SrTiO_3 could be the desirable visible-light photocatalysts. 展开更多
关键词 Zn Co a First-Principles Study and Zn-Codoped SrTiO_3 electronic Structure and Visible-Light Absorption of Transition Metals TiO Fe Mn Cr
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