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Modified Atomic Orbital Theory of the O+ Ion Originating from 2D0 and 4S0 Metastable States
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作者 Malick Sow Fatou Ndoye +3 位作者 Babou Diop Alassane Traoré Abdou Diouf Boubacar Sow 《Journal of Applied Mathematics and Physics》 2022年第6期1873-1886,共14页
We report in this paper energy positions of the 2D<sup>0</sup>_2s<sup>2</sup>2p<sup>2</sup>(<sup>1</sup>D)nd(<sup>2</sup>F);2D<sup>0</sup>_2s<... We report in this paper energy positions of the 2D<sup>0</sup>_2s<sup>2</sup>2p<sup>2</sup>(<sup>1</sup>D)nd(<sup>2</sup>F);2D<sup>0</sup>_2s<sup>2</sup>2p<sup>2</sup>(<sup>1</sup>D)nd(<sup>2</sup>D);2D<sup>0</sup>_2s<sup>2</sup>2p<sup>2</sup>(<sup>1</sup>D)nd(<sup>2</sup>P);2D<sup>0</sup>_2s<sup>2</sup>2p<sup>2</sup>(<sup>1</sup>D)ns(<sup>2</sup>D);2D<sup>0</sup>_2s<sup>2</sup>2p<sup>3</sup>(<sup>3</sup>D)np(<sup>2</sup>P);2D<sup>0</sup>_2s<sup>2</sup>2p<sup>3</sup>(<sup>3</sup>D<sup>0</sup>)np(<sup>2</sup>F), and 4S<sup>0</sup>_2s<sup>2</sup>2p<sup>3</sup>(<sup>5</sup>S<sup>0</sup>)np(<sup>4</sup>P) Rydberg series in the photoionization spectra originating from 2D<sup>0</sup> and 4S<sup>0</sup> metastable states of O<sup>+</sup> ion. Calculations are performed up to n = 20 using the Modified Orbital Atomic Theory (MAOT) [1]. The present results are compared to the experimental data of Aguilar et al. [2] which are the only available values. The accurate data presented in this work may be a useful guideline for future experimental and other theoretical studies. 展开更多
关键词 Semiempirical Calculations Modified Orbital atomic theory Electron Correlation Calculations Atoms and Ions Rydberg Series Quantum Defect
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Variational Calculation of the Doubly-Excited States Nsnp of He-Like Ions via the Modified Atomic Orbitals Theory 被引量:1
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作者 Abdourahmane Diallo Ibrahima Sakho +2 位作者 Jean Kouhissoré Badiane Mamadou Diouldé Ba Modou Tine 《Journal of Modern Physics》 2021年第2期105-121,共17页
In this paper, we have declined the formalism of the method of the Modified Atomic Orbital Theory (MAOT) applied to the calculations of energies of doubly excited states 2<em>snp</em>, 3<em>snp</e... In this paper, we have declined the formalism of the method of the Modified Atomic Orbital Theory (MAOT) applied to the calculations of energies of doubly excited states 2<em>snp</em>, 3<em>snp</em>, and 4<em>snp</em> Helium-like systems. Then we also applied the variational procedure of the Modified Atomic Orbital Theory to the computations of total energies, excitation energies of doubly-excited states 2<em>snp</em>, 3<em>snp</em>, 4<em>snp</em> types of Helium-like systems. The results obtained in this work are in good agreement with the experimental and theoretical values available. 展开更多
关键词 Modified atomic Orbital theory Doubly Excited States Excitation Energy Helium-Like Systems
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Theory to the Mystery of the Super Massive Black Holes
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作者 Ahti Rahikainen 《World Journal of Mechanics》 2023年第5期107-126,共20页
Vera Rubin measured the rotational speeds of galaxies, Ref. [1] 1983, and she found that the masses of galaxies were not enough to produce the measured speeds of rotation. Therefore, it was inferred that there must be... Vera Rubin measured the rotational speeds of galaxies, Ref. [1] 1983, and she found that the masses of galaxies were not enough to produce the measured speeds of rotation. Therefore, it was inferred that there must be an unknown matter which is many times the known visible and dark matter. In this study, the solution to the dark matter mystery of spiral galaxies is a four-dimensional mass in the space of four distance dimensions, coordinates: x,y,z,x', in which x' is the fourth distance dimension. The four-dimensional mass is a black hole, and it generates the main gravitation field of the galaxy. This mysterious black hole is located in the fourth dimension at the distance x' = X'. The rotational speed distribution curves of the galaxy NGC 3198 have been presented in Ref. [2]. The speed distribution curve of the galactic halo in that publication corresponds to the speed distribution curve of the four-dimensional black hole in this study. In order to find out how well this four-dimensional model functions, the speed distribution curve of the four-dimensional black hole was calculated, and it was compared with the halo curve of Ref. [2]. The conclusion was that the calculated speed distribution curve of the black hole was a good match to the halo curve of Ref. [2]. Furthermore, the rotational speed distribution curves of the four-dimensional black hole were calculated by using different values of the reduced distance X', which yielded at the distance X' = 0 a black hole of radius R = 7.7 × 10<sup>17</sup> m. By using the relativistic Lorentz transformation, it was shown in this study that a star falling into the four-dimensional black hole remains rotating it at near speed of light, and cannot fall into the actual black hole. 展开更多
关键词 Black Hole Galaxy Rotation Dark Matter Atom theory
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A Pursuit of Quantum Neuroscience’s Principles: Coherence Field Theory and the Physics of Mind 被引量:1
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作者 Eric Bond 《World Journal of Neuroscience》 2022年第2期57-67,共11页
Some basic physics of burgeoning quantum neuroscience is described. Anatomy of the neuron suggests that nonsynaptic mechanisms of signal transmittance occur via electric current acceleration and companion electromagne... Some basic physics of burgeoning quantum neuroscience is described. Anatomy of the neuron suggests that nonsynaptic mechanisms of signal transmittance occur via electric current acceleration and companion electromagnetic field fluctuation. I have named this mechanism of solution chemistry the ebb effect. Phase-locking between neural structure and electric fields that are emergent from cellular EM field fluctuations, in addition to feedback loops within neural networks, are the probable driver of macroscopic oscillation and flow shapes in the brain. CEMI (conscious electromagnetic information) theory is a promising framework for explaining intentionality and the spectrum of arousal as EM field effects. Relatively low frequency electromagnetic radiation is emitted by the accelerating electric currents of neurons. It is hypothesized that this EM radiation superpositions with molecular structure as it spreads to comprise percepts, the hybrid wavelengths of which form subjective images while wavelength vibrations result in subjective feel. These superposition arrays are termed a coherence field, and in combination with the synchronizing influence of quantum entanglement and electromagnetic fluctuations may constitute much of awareness’ substance. If conclusively verified, coherence field theory should have significance ranging from the treatment of perceptual disorders such as anosognosia to advancing foundational constructs like atomic theory. 展开更多
关键词 Quantum Coherence Wave Particle Duality SUPERPOSITION ENTANGLEMENT Electromagnetic Field Electromagnetic Radiation Ebb Effect CEMI atomic theory
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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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Four-Dimensional Mathematics Creates the Super Universe
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作者 Ahti Rahikainen 《World Journal of Mechanics》 2023年第7期135-148,共14页
In the common theory of the Universe, the redshift of the light wavelength from distant stars indicates the speed of the star. In this study, the model of the Universe is the surface volume of the four-dimensional sph... In the common theory of the Universe, the redshift of the light wavelength from distant stars indicates the speed of the star. In this study, the model of the Universe is the surface volume of the four-dimensional sphere, and the shape of the Universe results in the most of the redshift of light wavelength. Therefore, there is no dark energy accelerating the Universe. The surface of the four-dimensional sphere is a volume, and this volume is a good model for the Universe. The surface volume of the four-dimensional sphere has been explained by a model of four-dimensional cube, within which the forming of surface volume can be easily shown. The model of four-dimensional cube containing six side cubes is ingenious for explaining the structure of the four-dimensional Universe, but it is not enough because the four-dimensional cube has not six side cubes, but eight side cubes. Therefore, in this study a better method has been created to construct the four-dimensional cube. Our three-dimensional Universe is the surface of the four-dimensional sphere Universe. The volume of our three-dimensional Universe is finite, and beneath it is the infinite volume four-dimensional Super Universe. Two important basic formulae have been derived: The surface volume of the four-dimensional sphere is π<sup>3</sup>R<sup>3</sup> in which R is the radius of the sphere, and the fourth-power volume of the four-dimensional sphere is 1/4 π<sup>3</sup>R<sup>4</sup>. The volume of the Universe has been calculated π<sup>3</sup>R<sup>3</sup> = 62 × 10<sup>30</sup> ly<sup>3</sup>. Time as the fourth dimension of the space takes effect only near the speed of light, and therefore it has been ignored in this study. 展开更多
关键词 Mathematics of the Four-Dimensional Space Structure of the Universe Dark Matter Dark Energy Expansion of the Universe Big Bang Four-Dimensional Sphere Four-Dimensional Matter Atom theory
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Photoionization Study of the 2<i>s<sup>2</sup>2p<sup>2</sup>(<sup>1</sup>D)ns(<sup>2</sup>D), 2s<sup>2</sup>2p<sup>2</sup>(<sup>1</sup>D)nd(<sup>2</sup>P), 2s<sup>2</sup>2p<sup>2</sup>(<sup>1</sup>D)nd(<sup>2</sup>S), 2s<sup>2</sup>2p<sup>2</sup>(<sup>1</sup>S)nd<sup>2</sup>D</i>, and <i>2s<sup>2</sup>2p<sup>3</sup>(<sup>3</sup>P)np(<sup>2</sup>D)</i>Rydberg Series of O+ Ions via the Modified Atomic Orbital Theory 被引量:1
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作者 Malick Sow Fatou Ndoye +4 位作者 Alassane Traoré Abdou Diouf Boubacar Sow Youssou Gning Papa Amadou Lamine Diagne 《Journal of Modern Physics》 2021年第10期1435-1446,共12页
We report in this paper energy positions of the 2<em>P</em><span style="color:#222222;font-family:-apple-system, BlinkMacSystemFont, " font-size:14px;white-space:normal;background-color:#fffff... We report in this paper energy positions of the 2<em>P</em><span style="color:#222222;font-family:-apple-system, BlinkMacSystemFont, " font-size:14px;white-space:normal;background-color:#ffffff;"="">°</span>_2<em>s</em><sup>2</sup>2<em>p</em><sup>2</sup>(<sup>1</sup><em>D</em>)<em>nd</em> <sup>2</sup><em>P</em>, 2<em>P</em><span style="color:#222222;font-family:-apple-system, BlinkMacSystemFont, " font-size:14px;white-space:normal;background-color:#ffffff;"="">°</span>_2<em>s</em><sup>2</sup>2<em>p</em><sup>2</sup>(<sup>1</sup><em>D</em>)<em>nd</em> <sup>2</sup>S, 2<em>P</em><span style="color:#222222;font-family:-apple-system, BlinkMacSystemFont, " font-size:14px;white-space:normal;background-color:#ffffff;"="">°</span>_2<em>s</em><sup>2</sup>2<em>p</em><sup>2</sup>(<sup>1</sup><em>D</em>)<em>ns</em> <sup>2</sup>D, 2<em>P</em><span style="color:#222222;font-family:-apple-system, BlinkMacSystemFont, " font-size:14px;white-space:normal;background-color:#ffffff;"="">°</span>_2<em>s</em><sup>2</sup>2<em>p</em><sup>2</sup>(<sup>1</sup><em>S</em>)<em>nd</em> <sup>2</sup>D, and 2<em>P</em><span style="color:#222222;font-family:-apple-system, BlinkMacSystemFont, " font-size:14px;white-space:normal;background-color:#ffffff;"="">°</span>_2<em>s</em><sup>2</sup>2<em>p</em><sup>3</sup>(<sup>3</sup><em>P</em>)np <sup>2</sup><em>D</em> Rydberg series in the photoionization spectra originating from 2<em>P</em><span style="color:#222222;font-family:-apple-system, BlinkMacSystemFont, " font-size:14px;white-space:normal;background-color:#ffffff;"="">°</span> metastable state of O+ ions. Calculations are performed up to n = 30 using the Modified Orbital Atomic Theory (MAOT). The present results are compared to the experimental data of Aguilar which are the only available values. The accurate data presented in this work may be a useful guideline for future experimental and other theoretical studies. 展开更多
关键词 Semiempirical Calculations Modified Orbital atomic theory Electron Correlation Calculations Atoms and Ions Rydberg Series Quantum Defect
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Galaxy Rotation in the Space of Four Distance Dimensions 被引量:1
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作者 Ahti Rahikainen 《World Journal of Mechanics》 2020年第7期83-94,共12页
This study contains the solution of the dark matter mystery of spiral galaxies by using the space of four distance dimensions <i><span>x</span></i><span>, </span><i><span&g... This study contains the solution of the dark matter mystery of spiral galaxies by using the space of four distance dimensions <i><span>x</span></i><span>, </span><i><span>y</span></i><span>, </span><i><span>z</span></i><span>, </span><i><span>x</span></i><i><span>'</span></i><span "=""><span>, in which </span><i><span>x</span></i></span><i><span>'</span></i><span "=""><span> is the fourth distance dimension. The calculation of galaxy rotation has been presented in the space of four dimensions by using two dimensional section </span><i><span>x</span></i><span>, </span><i><span>x</span></i></span><i><span>'</span></i><span "=""><span> and three dimensional section </span><i><span>x</span></i><span>, </span><i><span>y</span></i><span>, </span><i><span>x</span></i></span><i><span>'</span></i><span "=""><span>. The four dimensional mass </span><i><span>M</span></i><span> which generates the main gravitation field of galaxy is located at the fourth dimension at the distance </span><i><span>x</span></i></span><i><span>'</span></i><span "=""><span> = </span><i><span>X</span></i></span><i><span>'</span></i><span "=""><span> and other dimensions are zero </span><i><span>x</span></i><span> = 0, </span><i><span>y</span></i><span> = 0, </span><i><span>z</span></i><span> = 0. The method to calculate the speed distribution curve of four dimensional mass </span><i><span>V</span><sub><span>M</span></sub></i><span>: the speed distribution curve </span><i><span>V</span><sub><span>M</span></sub> </i><span>is calculated by using the equation in which the gravitational force is equal to the centrifugal force </span></span><span "=""><span>of rotation. The solution of this equation yields the speed distribution</span><span> component </span><i><span>V</span><sub><span>M</span></sub></i><span> of the four dimensional mass </span><i><span>M</span></i><span> and the value of the mass </span><i><span>M.</span></i><span> In the publication </span></span><span>[1]</span><span "=""><span> has been presented rotational speed distributions curves of the galaxy NGC 3198. The speed distribution curve of galactic halo in that publication corresponds to the speed distribution curve </span><i><span>V</span><sub><span>M</span></sub></i><span> of four dimensional mass </span><i><span>M</span></i><span> of this study. In order to find out how well this four dimensional model functions, the speed distribution curve </span><i><span>V</span><sub><span>M</span></sub></i><span> of four dimensional mass </span><i><span>M</span></i><span> has been calculated by using two pairs of rotational radius and speed values. The conclusions and findings: the calculated distribution curve </span><i><span>V</span><sub><span>M</span></sub></i><span> was a good match for the halo curve of the publication </span></span><span>[1]</span><span background:lime;"=""></span><span minion="" pro="" capt","serif";background:lime;"=""></span><span "=""><span>. Furthermore, four rotational speed distribution curve </span><i><span>V</span><sub><span>M</span></sub></i><span> was calculated using different values of the distance </span><i><span>X</span></i></span><i><span>'</span></i><span>, which yielded different values for the maximum radius of galaxy. In this manner the different galaxy models of the publication </span><span minion="" pro="" capt","serif";"=""><span> </span><span style="background:lime;"></span></span>[2]<sup><span background:lime;"=""></span><span minion="" pro="" capt","serif";background:lime;"=""></span></sup><span><sup> </sup>were obtained. By that means the solution of dark matter mystery has been proved.</span> 展开更多
关键词 Galaxy Rotation Dark Matter Atom theory
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Density Functional Study of the C Atom Adsorption on the α-Fe_2O_3 (001) Surface 被引量:2
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作者 董长青 张晓磊 杨勇平 《Chinese Journal of Structural Chemistry》 SCIE CAS CSCD 2011年第1期17-24,共8页
The adsorption of C atoms on the α-Fe2O3(001) surface was studied based on density function theory(DFT) ,in which the exchange-correlation potential was chosen as the PBE(Perdew,Burke and Ernzerhof) generalized... The adsorption of C atoms on the α-Fe2O3(001) surface was studied based on density function theory(DFT) ,in which the exchange-correlation potential was chosen as the PBE(Perdew,Burke and Ernzerhof) generalized gradient approximation(GGA) with a plane wave basis set. Upon the optimization on different adsorption sites with coverage of 1/20 and 1/5 ML,it was found that the adsorption of C atoms on the α-Fe2O3(001) surface was chemical adsorption. The coverage can affect the adsorption behavior greatly. Under low coverage,the most stable adsorption geometry lied on the bridged site with the adsorption energy of about 3.22 eV; however,under high coverage,it located at the top site with the energy change of 8.79 eV. Strong chemical reaction has occurred between the C and O atoms at this site. The density of states and population analysis showed that the s,p orbitals of C and p orbital of O give the most contribution to the adsorption bonding. During the adsorption process,O atom shares the electrons with C,and C can only affect the outermost and subsurface layers of α-Fe2O3; the third layer can not be affected obviously. 展开更多
关键词 α-Fe2O3 (001) C atom density functional theory adsorption chemical looping combustion
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Curvature and Size Effects on Reactivities of Mono-to Octa-vacancies in a(5,5) Single-walled Carbon Nanotube 被引量:1
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作者 贾桂霄 李磊 +3 位作者 王晓霞 孙松松 包金小 安胜利 《Chinese Journal of Structural Chemistry》 SCIE CAS CSCD 2017年第4期621-630,共10页
Defect curvature was developed based on our previously proposed direction curvature theory. Defect curvature, as a universal criterion, was used to identify vacancy formation energies E_f of mono-vacancies to octa-vac... Defect curvature was developed based on our previously proposed direction curvature theory. Defect curvature, as a universal criterion, was used to identify vacancy formation energies E_f of mono-vacancies to octa-vacancies in a(5,5) tube. An ab initio calculation results showed that E_f decreased with increasing the defect curvature K_(V_s)(s = 1~8). The structures with removed carbon atoms along zigzag chain or the tubular axis were the most stable in each kind of Vs, because their corresponding K_(V_s) was the largest. In addition, local product structures disturbed the variation rule of E_f as K_(V_s). There was an odd-even oscillation rule in the smallest E_f among each kind of Vs as the s value and vacancies V2, V4 and V6 were more stable. The stabilities of the related vacancy structures were confirmed by two dissociation processes. 展开更多
关键词 defect curvature atomic vacancies vacancy formation energies density functional theory
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Studies on the Quantitative Structure-activity Relationship of Toxicity of Chlorophenol Serial Compounds in the ab initio Methods and Substitutive Position of Chlorine Atom (N_(PCS)) 被引量:15
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作者 ZHENG Qing WANG Lian-Sheng 《Chinese Journal of Structural Chemistry》 SCIE CAS CSCD 北大核心 2007年第8期933-938,共6页
20 Quantum chemical parameters of chlorophenol compounds were fully optimized by using B3LYP method on both 6-31G^* and 6-311G^* basis sets. These structural parameters are taken as theoretical descriptors, and the ... 20 Quantum chemical parameters of chlorophenol compounds were fully optimized by using B3LYP method on both 6-31G^* and 6-311G^* basis sets. These structural parameters are taken as theoretical descriptors, and the experimental data of 20 compounds' aquatic photogen toxicity(-lgEC50) are used to perform stepwise regression in order to obtain two predicted -lgEC50 correlation models whose correlation coefficients R^2 are respectively 0.9186 and 0.9567. In addition, parameters of chlorine atom's substitutive positions and their correlations (NPCs) are taken as descriptors to obtain another predicted -lgEC50 model with the correlation coefficient R2 of 0.9444. Correlation degree of each independent variable in the three models is verified by using variance inflation factors (VIF) and t value. In the cross-validation method, cross-validation coefficients q^2 of 3 models are respectively 0.8748, 0.9119 and 0.8993, which indicates that the relativity and prediction ability of this model are superior to those of the model obtained by topological and BLYP methods. 展开更多
关键词 chlorophenol toxicity (-lgEC50) linear dissolving energy theory density functional theory (DFT) substitutive position of chlorine atom (NPCS) QSAR
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The Solution to the Dark Energy Mystery in the Universe of Four Distance Dimensions
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作者 Ahti Rahikainen 《World Journal of Mechanics》 2021年第5期95-110,共16页
This study is a continuation of the solution to the dark matter mystery in the earlier study. In that study, the theoretical four-dimensional mass generates similar galaxy rotations as were measured. This proves that ... This study is a continuation of the solution to the dark matter mystery in the earlier study. In that study, the theoretical four-dimensional mass generates similar galaxy rotations as were measured. This proves that the theory of four-dimensional mass is correct, especially as all the calculations are basic mechanics and easy to understand. Most of the mass and energy in the Universe is unknown. The common knowledge is that the ordinary mass is only about 5%, the dark matter that rotates the galaxies comprises 26%, and dark energy that expands the Universe at an accelerating speed is 69%. This study solves the mystery of dark energy by using the structure of the four-dimensional Universe. The theory of the Universe expanding at an accelerating speed has been based on the redshift measurements, in which the redshift of light from distant galaxies increases at an accelerating rate. Therefore, it has been inferred that the whole Universe expands at an accelerating speed. In this study, the model of the Universe is the surface volume of the four-dimensional spherical Universe. This type of structure of the Universe creates the same kind of an accelerating redshift increase which has been measured. In order to prove this theory, the model of the surface volume of the four-dimensional Universe was constructed, the equation of the redshift caused by this Universe was solved, and the theoretical equation was shown to be the same as the measured redshift in the Universe. The measured redshift in the Universe was obtained from the derivative of the model of the expanding Universe. A similar model of the Universe has been published by NASA. The four-dimensional model of the Universe in this study yielded the Universe that was found to have decelerating expansion at this point of time, and a Big Bang that was not very big. 展开更多
关键词 Dark Matter Dark Energy Expansion of Universe Big Bang Four-Dimensional Sphere Four-Dimensional Matter Atom theory
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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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Atom Response Theory of Nonlinear Optical Responses and Its Applications
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作者 程曦月 皇甫明焕 +1 位作者 洪茂椿 邓水全 《Chinese Journal of Structural Chemistry》 SCIE CAS CSCD 2020年第12期2172-2181,2056,共11页
Second-order nonlinear optical(NLO)crystalline materials are fundamentally and technologically important for their ability to double or triple the frequency of lasers.This article provides a brief review of the atom r... Second-order nonlinear optical(NLO)crystalline materials are fundamentally and technologically important for their ability to double or triple the frequency of lasers.This article provides a brief review of the atom response theory(ART)of NLO responses recently developed on the basis of the partial response functional method.The ART analysis enables one to quantitatively evaluate the contributions of individual constituent atoms to the second harmonic generation(SHG)response of a NLO crystal material on the basis of first principles DFT calculations.The general partitioning principles developed in our recent work provide the conceptual foundation for determining the functional motifs of SHG responses.In this mini review we will focus on the concepts and principles as well as on applications with examples.Some practically important empirical rules resulting from the ART studies will also be reviewed. 展开更多
关键词 atom response theory nonlinear optical materials functional motif first-principles calculation
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Theoretical Study of the Radical Scavenging Activity of Shikonin and Its Derivatives
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作者 靳瑞岌 李杰 《Chinese Journal of Chemistry》 SCIE CAS CSCD 2012年第1期84-90,共7页
A series of shikonin derivatives have been designed and their radical scavenging activity has been characterized by the B3LYP/6-31 +G(d) approach. The hydrogen bond properties of the studied structures were investi... A series of shikonin derivatives have been designed and their radical scavenging activity has been characterized by the B3LYP/6-31 +G(d) approach. The hydrogen bond properties of the studied structures were investigated using the atoms in molecules (AIM) theory. The calculated results reveal that the hydrogen bond is important for good scavenging activity. The introduction of electron-drawing (electron-donating) groups increases (decreases) the scavenging activities of radical and radical cations of shikonin derivatives. Shikonin derivatives appear to be good candidates for the single-electron-transfer mechanism, particularly for -N(CH3)2 derivative. Taking this system as an example, we present an efficient method for the investigation of radical scavenging activity from theoretical point of view. With the current work, we hope to highlight the radical scavenging activity of hydroxynaphtho- quinones derivatives and stimulate the interest for further studies and exploitation in pharmaceutical industry. 展开更多
关键词 shikonin derivatives radical scavenging activity hydrogen atom transfer mechanism single electrontransfer mechanism atoms in molecules theory (AIM)
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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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Theoretical Studies on the Dihydrogen Bonding Between Shortchain Hydrocarbon and Magnesium Hydride
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作者 LI Li BAI Fuquan ZHANG Hongxing 《Chemical Research in Chinese Universities》 SCIE CAS CSCD 2014年第5期831-836,共6页
The C--H…H dihydrogen-bonded complexes of methane, ethylene, acetylene, and their derivatives with magnesium hydride were systematically investigated at MP2/aug-cc-PVTZ level. The results confirm that the strength of... The C--H…H dihydrogen-bonded complexes of methane, ethylene, acetylene, and their derivatives with magnesium hydride were systematically investigated at MP2/aug-cc-PVTZ level. The results confirm that the strength of dihydrogen bonding increases in the following order of proton donors: C(sp3)-H〈C(sp2)-H〈C(sp)-H and chlorine substituents enhance the C-H…H interaction. In the majority of the complexes with a cyclic structure, the Mg-H proton-accepting bond is more sensitive to the surroundings than C-H proton-donating bond. The nature of the electrostatic interaction in these C-H…H dihydrogen bonds was also unveiled by means of the atoms in mo- lecules(AIM) analysis. The natural bond orbital(NBO) analysis suggests that the charge transfer in the cyclic com- plexes is characteristic of dual-channel. The direction of the net charge transfer in the cyclic complexes is contrary to that previously found in dihydrogen bonded systems. 展开更多
关键词 Dihydrogen bond Atom in molecule(AIM) theory Bond critical point Natural bond orbital(NBO) CHARGETRANSFER
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