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Spectroscopy and molecule opacity investigation on excited states of SiS
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作者 李瑞 吕浩男 +3 位作者 桑纪群 刘晓华 梁桂颖 吴勇 《Chinese Physics B》 SCIE EI CAS CSCD 2024年第5期381-387,共7页
The SiS molecule,which plays a significant role in space,has attracted a great deal of attention for many years.Due to complex interactions among its low-lying electronic states,precise information regarding the molec... The SiS molecule,which plays a significant role in space,has attracted a great deal of attention for many years.Due to complex interactions among its low-lying electronic states,precise information regarding the molecular structure of SiS is limited.To obtain accurate information about the structure of its excited states,the high-precision multireference configuration interaction(MRCI)method has been utilized.This method is used to calculate the potential energy curves(PECs)of the 18Λ–S states corresponding to the lowest dissociation limit of SiS.The core–valence correlation effect,Davidson’s correction and the scalar relativistic effect are also included to guarantee the precision of the MRCI calculation.Based on the calculated PECs,the spectroscopic constants of quasi-bound and bound electronic states are calculated and they are in accordance with previous experimental results.The transition dipole moments(TDMs)and dipole moments(DMs)are determined by the MRCI method.In addition,the abrupt variations of the DMs for the 1^(5)Σ^(+)and 2^(5)Σ^(+)states at the avoided crossing point are attributed to the variation of the electronic configuration.The opacity of SiS at a pressure of 100 atms is presented across a series of temperatures.With increasing temperature,the expanding population of excited states blurs the band boundaries. 展开更多
关键词 SIS OPACITY excited state spectroscopic constant configuration interaction
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Two-proton radioactivity from excited states of proton-rich nuclei within Coulomb and Proximity Potential Model 被引量:1
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作者 De-Xing Zhu Yang-Yang Xu +3 位作者 Li-Jia Chu Xi-Jun Wu Biao He Xiao-Hua Li 《Nuclear Science and Techniques》 SCIE EI CAS CSCD 2023年第9期1-7,共7页
In the present work,we extend the Coulomb and Proximity Potential Model(CPPM)to study two-proton(2p)radioactivity from excited states while the proximity potential is chosen as AW95 proposed by Aage Withner in 1995.De... In the present work,we extend the Coulomb and Proximity Potential Model(CPPM)to study two-proton(2p)radioactivity from excited states while the proximity potential is chosen as AW95 proposed by Aage Withner in 1995.Demonstration reveals that the theoretical results acquired by CPPM exhibit a high level of consistency with prior theoretical models such as the unified fission model(UFM),generalized liquid-drop model(GLDM)and effective liquid-drop model(ELDM).Furthermore,within the CPPM,we predicted the half-lives of potential 2p radioactive nuclei for which experimental data are currently unavailable.The predicted results were then assessed,compared with UFM,ELDM and GLDM models,and examined in detail. 展开更多
关键词 2p radioactivity CPPM HALF-LIVES excited state
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Role of excited states in helium-like ions on high-order harmonic generation
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作者 罗江华 肖佳俊 《Chinese Physics B》 SCIE EI CAS CSCD 2023年第11期408-412,共5页
We theoretically investigate high-order harmonic generation(HHG) of helium(He), lithium cation(Li+), and beryllium dication(Be2+) using the time-dependent Hartree–Fock method to solve the three-dimensional time-depen... We theoretically investigate high-order harmonic generation(HHG) of helium(He), lithium cation(Li+), and beryllium dication(Be2+) using the time-dependent Hartree–Fock method to solve the three-dimensional time-dependent Schr ¨odinger equation. It is found that the intensity of the HHG increases significantly from a certain harmonic order below the ionization threshold, and the initial position of the enhancement does not depend on the intensity or the wavelength of the driving laser field. Further analysis shows that excited states play an important role on this enhancement,consistent with the excited-state tunneling mechanism [Phys. Rev. Lett. 116 123901(2016)]. Our results unambiguously show that excited-state tunneling is essential for understanding the enhancement of HHG. Accordingly, a four-step model is herein proposed to illustrate the multiphoton excitation effect in helium-like ions, which enriches the physics of HHG enhancement. 展开更多
关键词 high-order harmonic generation ultrafast phenomena excited states
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A TD-DFT Study for the Excited State Calculations of Microhydration of N-Acetyl-Phenylalaninylamide (NAPA)
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作者 Md. Alauddin Joya Datta Ripa 《Computational Chemistry》 CAS 2023年第2期37-52,共16页
Investigating the impact of microhydration on the excited-states and electronic excitation properties of biomolecules has remained one of the important yet challenging aspects of science because of the complexity of d... Investigating the impact of microhydration on the excited-states and electronic excitation properties of biomolecules has remained one of the important yet challenging aspects of science because of the complexity of developing models. However, with the advent of computational chemistry methods such as TD-DFT, many useful insights about the electronic excitation energy and excited-state nature of biomolecules can be explored. Accordingly, in our study, we have incorporated the TD-DFT/wB97XD/cc-pVTZ method to study the excited state properties of N-acetyl phenylalanine amide (NAPA-A(H<sub>2</sub>O) <sub>n</sub>) (n = 1 to 4) clusters from ground to the tenth lowest gaseous singlet excited state. We found that the C=O bond length gradually increases both in N-terminal amide and C-terminal amide after the sequential addition of water molecules because of intermolecular H-bonding and this intermolecular H-bonding becomes weaker after the sequential addition of H<sub>2</sub>O molecules. The UV absorption maxima of NAPA-A (H<sub>2</sub>O)<sub>n</sub> (n = 1 - 4) clusters consisted of two peaks that are S<sub>5</sub>←S<sub>0</sub> (1<sup>st</sup> absorption) and S<sub>6</sub>←S<sub>0</sub> (2<sup>nd</sup> absorption) excitations. The first absorption maxima were blue-shifted with the increase in oscillator strength. This means that strong H-bonds reduce the charge transfer and make clusters more rigid. On the other hand, the second absorption maxima were red-shifted with the decrease in oscillator strength. In the ECD spectra, the negative bands indicate the presence of an amide bond and L-configuration of micro hydrated NAPA-A clusters. Finally, our calculated absorption and fluorescence energy confirm that all the NAPA-A (H<sub>2</sub>O) <sub>n</sub> (n = 0 - 4) clusters revert to the ground state from the fluorescent state by emitting around 5.490 eV of light. 展开更多
关键词 excited state H-BONDING Micro Hydration Absorption and Fluorescence Energy
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Characterization of the Excited State on Methanol/Ti02(110) Interface 被引量:1
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作者 王志强 郝群庆 +5 位作者 毛新春 周传耀 马志博 任泽峰 戴东旭 杨学明 《Chinese Journal of Chemical Physics》 SCIE CAS CSCD 2015年第2期123-127,I0001,共6页
The electronic structure of methanol/TiO2(ll0) interface has been studied by photoemis- sion spectroscopy. The pronounced resonance which appears at 5.5 eV above the Fermi level in two-photon photoemission spectrosc... The electronic structure of methanol/TiO2(ll0) interface has been studied by photoemis- sion spectroscopy. The pronounced resonance which appears at 5.5 eV above the Fermi level in two-photon photoemission spectroscopy (2PPE) is associated with the photocatalyzed dissociation of methanol at fivefold coordinated Ti sites (Ti5c) on TiO2 (110) surface [Chem- ical Science 1, 575 (2010)]. To check whether this resonance signal arises from initial or intermediate states, photon energy dependent 2PPE and comparison between one-photon photoemission spectroscopy and 2PPE have been performed. Both results consistently sug- gest the resonance signal originates from the initially unoccupied intermediate states, i.e., excited states. Dispersion measurements suggest the excited state is localized. Time-resolved studies show the lifetime of the excited state is 24 fs. This work presents comprehensive char- acterization of the excited states on methanol/TiO2(110) interface, and provides elaborate experimental data for the development of theoretical methods in reproducing the excited states on TiO2 surfaces and interfaces. 展开更多
关键词 Titanium dioxide excited states Two-photon photoemission TIME-RESOLVED
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Experimental and Theoretical Investigation on Excited State Intramolecular Proton Transfer Coupled Charge Transfer Reaction of Baicalein
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作者 胡闪闪 刘琨 +2 位作者 丁倩倩 彭伟 陈茂笃 《Chinese Journal of Chemical Physics》 SCIE CAS CSCD 2014年第1期51-56,I0003,共7页
The excited state intramolecular proton transfer (ESIPT) coupled charge transfer of baicalein has been investigated using steady-state spectroscopic experiment and quantum chemistry calculations. The absence of the ... The excited state intramolecular proton transfer (ESIPT) coupled charge transfer of baicalein has been investigated using steady-state spectroscopic experiment and quantum chemistry calculations. The absence of the absorption peak from S1 excited state both in the experi-mental and calculated absorption spectra indicates that S1 is a dark state. The dark excited state S1 results in the very weak fluorescence of solid baicalein in the experiment. The fron- tier molecular orbital and the charge difference densities of baicalein show clearly that the S1 state is a charge-transfer state whereas the S2 state is a locally excited state. The only one stationary point on the potential energy profile of excited state suggests that the ESIPT reaction of baicalein is a barrierless process. 展开更多
关键词 excited state intramolecular proton transfer Intramolecular charge transfer Time-dependent density functional theory Dark state BAICALEIN
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Behaviours of the excited states 1s^2 np along lithium isoelectronic sequence from Z=11 to 20 被引量:3
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作者 胡木宏 王治文 《Chinese Physics B》 SCIE EI CAS CSCD 2008年第3期908-914,共7页
Based on the obtained energy values of 1s^2np (n≤ 9) states for lithium-like systems from Z=11 to 20 (by the authors of this paper: Hu M H and Wang Z W 2004 Chin. Phys. 13 662), this paper determines the quantum... Based on the obtained energy values of 1s^2np (n≤ 9) states for lithium-like systems from Z=11 to 20 (by the authors of this paper: Hu M H and Wang Z W 2004 Chin. Phys. 13 662), this paper determines the quantum defects, as slowly varying function of energy, of this Rydberg series. Using them as input, it can predict the energies of any highly excited states below the ionization threshold for this series a^cording to the quantum defect theory. The regularities of variation for quantum defects of the series along this isoelectronic sequence are physically analysed and discussed. The screening parameters, which are equal to the effective screening charge of the core-electrons, are also obtained. 展开更多
关键词 lithium-like system excited state quantum defect screening parameter
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Measurement of Photoionization Cross Sections of the Excited States of Titanium 被引量:3
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作者 Jia-jun Yang Xing-yong Hu +7 位作者 Hong-xia Wu Jian-mei Fan Ran Cong Yi Cheng Xue-han Ji Guan-xin Yao Xian-feng Zheng Zhi-feng Cui 《Chinese Journal of Chemical Physics》 SCIE CAS CSCD 2009年第6期615-620,J0002,共7页
Resonance-enhanced multiphoton ionization of the titanium atoms has been investigated in the 293 321 nm wavelength. We couple a laser-ablated metal target into a molecular beam to produce free atoms. Ions produced fro... Resonance-enhanced multiphoton ionization of the titanium atoms has been investigated in the 293 321 nm wavelength. We couple a laser-ablated metal target into a molecular beam to produce free atoms. Ions produced from photoionization of the neutral atoms are monitored by a home-built time-of-flight mass spectrometer. Photoionization cross sections of the excited states of Ti I were deduced from the dependence of the ion signal intensity on the laser intensity for photon energies close to the ionization threshold. The values obtained range from 0.2 Mb to 6.0 Mb. No significant isotope-dependence was found from measurements of the photoionization cross sections of ^46Ti, ^47Ti, and ^48Ti. 展开更多
关键词 Photoionization cross section excited state TITANIUM
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Two-proton radioactivity of the excited state within the Gamow-like and modified Gamow-like models 被引量:2
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作者 De-Xing Zhu Yang-Yang Xu +3 位作者 Hong-Ming Liu Xi-Jun Wu Biao He Xiao-Hua Li 《Nuclear Science and Techniques》 SCIE EI CAS CSCD 2022年第10期1-10,共10页
In this study,we systematically investigated the two-proton(2p)radioactivity half-lives from the excited state of nuclei near the proton drip line within the Gamowlike model(GLM)and modified Gamow-like model(MGLM).The... In this study,we systematically investigated the two-proton(2p)radioactivity half-lives from the excited state of nuclei near the proton drip line within the Gamowlike model(GLM)and modified Gamow-like model(MGLM).The calculated results were highly consistent with the theoretical values obtained using the unified fission model[Chin.Phys.C 45,124105(2021)],effective liquid drop model,and generalized liquid drop model[Acta Phys.Sin 71,062301(2022)].Furthermore,utilizing the GLM and MGLM,we predicted the 2p radioactivity halflives from the excited state for some nuclei that are not yet available experimentally.Simultaneously,by analyzing the calculated results from these theoretical models,it was found that the half-lives are strongly dependent on Qand l. 展开更多
关键词 2p radioactivity Gamow-like model Halflife excited state
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Role of excited states in the elliptically polarized harmonic generation 被引量:1
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作者 杜洪川 文一震 +1 位作者 王小山 胡碧涛 《Chinese Physics B》 SCIE EI CAS CSCD 2014年第3期219-223,共5页
We theoretically investigate the contribution of the excited state to the ellipticity of the harmonics from H+ at different orientation angles irradiated by a linearly polarized laser pulse. It is found that the firs... We theoretically investigate the contribution of the excited state to the ellipticity of the harmonics from H+ at different orientation angles irradiated by a linearly polarized laser pulse. It is found that the first excited state has a significant influence to the ellipticity of the harmonics, and the contribution of higher excited states to the ellipticity can be neglected. Moreover, the conclusion is not dependent on the laser intensity. 展开更多
关键词 high-order harmonic generation intense laser excited state ELLIPTICITY
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Adiabatic Potential Energy Surfaces and Photodissociation Mechanisms for Highly Excited States of H_(2)O 被引量:1
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作者 Feng An Shanyu Han +2 位作者 Xixi Hu Kaijun Yuan Daiqian Xie 《Chinese Journal of Chemical Physics》 SCIE EI CAS CSCD 2022年第1期104-116,I0063,共14页
Full-dimensional adiabatic potential energy surfaces of the electronic ground state X and nine excited states A,I,B,C,D,D',D'',E' and F of H_(2)O molecule are developed at the level of internally contr... Full-dimensional adiabatic potential energy surfaces of the electronic ground state X and nine excited states A,I,B,C,D,D',D'',E' and F of H_(2)O molecule are developed at the level of internally contracted multireference configuration interaction with the Davidson correction.The potential energy surfaces are fitted by using Gaussian process regression combining permutation invariant polynomials.With a large selected active space and extra diffuse basis set to describe these Rydberg states,the calculated vertical excited energies and equilibrium geometries are in good agreement with the previous theoretical and experimental values.Compared with the well-investigated photodissociation of the first three low-lying states,both theoretical and experimental studies on higher states are still limited.In this work,we focus on all the three channels of the highly excited state,which are directly involved in the vacuum ultraviolet photodissociation of water.In particular,some conical intersections of D-E',E'-F,A-I and I-C states are clearly illustrated for the first time based on the newly developed potential energy surfaces(PESs).The nonadiabatic dissociation pathways for these excited states are discussed in detail,which may shed light on the photodissociation mechanisms for these highly excited states. 展开更多
关键词 Adiabatic potential energy surface Highly excited state Photodissociation mechanism Conical intersection Gaussian process regression
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Excited state refraction of C_(70)/toluene studied by using 4f coherent imaging system with phase object 被引量:1
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作者 刘南春 石光 +1 位作者 杨俊义 宋瑛林 《Chinese Physics B》 SCIE EI CAS CSCD 2011年第1期304-309,共6页
Dynamic nonlinearities of C70/toluene solution are measured and analysed by an improved picosecond timeresolved pump-probe system based on a nonlinear imaging technique with phase object. The photophysical parameters ... Dynamic nonlinearities of C70/toluene solution are measured and analysed by an improved picosecond timeresolved pump-probe system based on a nonlinear imaging technique with phase object. The photophysical parameters are determined by the five-level model, which is adopted to interpret the experimental data. The change of refraction index per unit density of the excited state obtained by a numerically simulation is a critical factor to determine the nonlinear behaviour of C70 in picosecond time regime. 展开更多
关键词 4f system excited state refraction C70/toluene solution refraction index per unit density
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Time-dependent Density Functional Theory Study on the Electronically Excited States of N-Methylformamide in Aqueous Solution 被引量:1
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作者 尹淑慧 马超 +4 位作者 何香怡 郭明星 许雪松 宋哲 韩易轩 《Chinese Journal of Structural Chemistry》 SCIE CAS CSCD 2012年第7期925-932,共8页
Excited-state hydrogen-bonding dynamics of N-methylformamide (NMF) in water has been investigated by time-dependent density functional theory (TDDFT) method. The ground-state geometry optimizations were calculated... Excited-state hydrogen-bonding dynamics of N-methylformamide (NMF) in water has been investigated by time-dependent density functional theory (TDDFT) method. The ground-state geometry optimizations were calculated by density functional theory (DFT) method, while the electronic transition energies and corresponding oscillation strengths of the low-lying electronically excited states of isolated NMF, water monomers and the hydrogen-bonded NMF-H 2 O were calculated by TDDFT method. According to Zhao's rule on the excited-state hydrogen bonding dynamics, our results demonstrate that the intermolecular hydrogen bond C=O···O-H is strengthened and weakened in different electronically excited states. The hydrogen bond strengthening and weakening in the electronically excited state plays an important role in the photophysics of NMF in solutions. 展开更多
关键词 hydrogen bond excited state NMF DFT/TDDFT
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Temperature and hydrogen-like impurity effects on the excited state of the strong coupling bound polaron in a CsI quantum pseudodot 被引量:2
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作者 Jing-Lin Xiao 《Chinese Physics B》 SCIE EI CAS CSCD 2017年第2期399-402,共4页
With hydrogen-like impurity(HLI) located in the center of Cs I quantum pseudodot(QPD) and by using the variational method of Pekar type(VMPT), we investigate the first-excited state energy(FESE), excitation en... With hydrogen-like impurity(HLI) located in the center of Cs I quantum pseudodot(QPD) and by using the variational method of Pekar type(VMPT), we investigate the first-excited state energy(FESE), excitation energy and transition frequency of the strongly-coupled bound polaron in the present paper. Temperature effects on bound polaron properties are calculated by employing the quantum statistical theory(QST). According to the present work's numerical results, the FESE, excitation energy and transition frequency decay(amplify) with raising temperature in the regime of lower(higher)temperature. They are decreasing functions of Coulomb impurity potential strength. 展开更多
关键词 temperature effect bound polaron CsI quantum pseudodot quantum statistical theory excited state
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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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Modified Atomic Orbital Calculations of Energy of the(2s^(2)^(1)S)Ground-State,the(2p^(2)^(1)D);(3d^(2)^(1)G)and(4f^(2)^(1)I)Doubly Excited States of Helium Isoelectronic Sequence from H-to Ca^(18+) 被引量:1
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作者 Malick Sow Ibrahima Sakho +9 位作者 Boubacar Sow Abdou Diouf Youssou Gning Babou Diop Matabara Dieng Abdourahmane Diallo Mamadou DiouldéBa Jean KouhissoréBadiane Mamadi Biaye Ahmadou Wagué 《Journal of Applied Mathematics and Physics》 2020年第1期85-99,共15页
We report in this paper the ground-state energy 2s^(2)^(1)S and total energies of doubly excited states 2p^(2)^(1)D,3d^(2)^(1)D,4f^(2)^(1)I of the Helium isoelectronic sequence from H-to Ca^(18+).Calculations are perf... We report in this paper the ground-state energy 2s^(2)^(1)S and total energies of doubly excited states 2p^(2)^(1)D,3d^(2)^(1)D,4f^(2)^(1)I of the Helium isoelectronic sequence from H-to Ca^(18+).Calculations are performed using the Modified Atomic Orbital Theory(MAOT)in the framework of a variational procedure.The purpose of this study required a mathematical development of the Hamiltonian applied to Slater-type wave function[1]combining with Hylleraas-type wave function[2].The study leads to analytical expressions which are carried out under special MAXIMA computational program.This first proposed MAOT variational procedure,leads to accurate results in good agreement as well as with available other theoretical results than experimental data.In the present work,a new correlated wave function is presented to express analytically the total energies for the 2s21S ground state and each doubly 2p^(2)^(1)D,3d^(2)^(1)D,4f^(2)^(1)I excited states in the He-like systems.The present accurate data may be a useful guideline for future experimental and theoretical studies in the(nI^(2))systems. 展开更多
关键词 Modified Atomic Orbital Theory Variational Calculations Correlated Wavefunction ENERGIES GROUND-state Doubly excited states Helium Isoelectronic Sequence Atoms and Ions
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Influence of Molecular Stacking Pattern on Excited State Dynamics of Copper Phthalocyanine Films
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作者 Meng Li Wen-hui Li +8 位作者 Yu-jie Hu Jing Leng Wen-ming Tian Chun-yi Zhao Jun-xue Liu Rong-rong Cui Sheng-ye Jin Chuan-hui Cheng Shu-lin Cong 《Chinese Journal of Chemical Physics》 SCIE EI CAS CSCD 2022年第6期900-906,I0073,共8页
Photophysical processes occurring within organic semiconductors is important for designing and fabricating organic solar cells.Copper phthalocyanine(CuPc)is a typical electron acceptor.In this work,the triplet exciton... Photophysical processes occurring within organic semiconductors is important for designing and fabricating organic solar cells.Copper phthalocyanine(CuPc)is a typical electron acceptor.In this work,the triplet exciton lifetime is prolonged by altering the molecular stacking pattern of the CuPc film.For CuPc thin films,the excited state decays are mainly determined by the triplet-triplet annihilation process.The ultrafast transient absorption measurements indicate that the primary annihilation mechanism is one-dimensional exciton diffusion collision destruction.The decay kinetics show a clearly time-dependent annihilation rate constant withγ∝t^(-1/2).Annihilation rate constants are determined to beγ0=(2.87±0.02)×10^(-20)cm^(3)·s^(-1/2)and(1.42±0.02)×10^(-20)cm^(3)·s^(-1/2)for upright and lyingdown configurations,respectively.Compared to the CuPc thin film with an upright configuration,the thin film with a lying-down configuration shows longer exciton lifetime and higher absorbance,which are beneficial to organic solar cells.The results in this work have important implications on the design and mechanistic understanding of organic optoelectronic devices. 展开更多
关键词 CUPC PHOTOPHYSICS excited state Triplet-triplet annihilation Organic solar cell
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Evaluating First-Order Molecular Properties of Delocalized Ionic or Excited States in Molecular Aggregates by Renormalized Excitonic Method
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作者 Yun-hao Liu Ke Wang Hai-bo Ma 《Chinese Journal of Chemical Physics》 SCIE CAS CSCD 2021年第6期670-682,I0001,共14页
In the past few years,the renormalized excitonic model(REM)approach was developed as an efficient low-scaling ab initio excited state method,which assumes the low-lying excited states of the whole system are a linear ... In the past few years,the renormalized excitonic model(REM)approach was developed as an efficient low-scaling ab initio excited state method,which assumes the low-lying excited states of the whole system are a linear combination of various single monomer excitations and utilizes the effective Hamiltonian theory to derive their couplings.In this work,we further extend the REM calculations for the evaluations of first-order molecular properties(e.g.charge population and transition dipole moment)of delocalized ionic or excited states in molecular aggregates,through generalizing the effective Hamiltonian theory to effective operator representation.Results from the test calculations for four different kinds of one dimensional(1D)molecular aggregates(ammonia,formaldehyde,ethylene and pyrrole)indicate that our new scheme can efficiently describe not only the energies but also wavefunction properties of the low-lying delocalized electronic states in large systems. 展开更多
关键词 Renormalization group Frenkel exciton WAVEFUNCTION excited state Mulliken charge Transition dipole moment
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Ultrafast Excited State Dynamics of Biliverdin Dimethyl Ester Coordinate with Zinc Ions
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作者 Zhuang Chen Yang-yi Liu +1 位作者 Xiao-xiao He Jin-quan Chen 《Chinese Journal of Chemical Physics》 SCIE CAS CSCD 2020年第1期69-74,I0030-I0033,共10页
As one of the biological endogenous pigments,biliverdin(BV)and its dimethyl ester(BVE)have extremely weak uorescence in solution with quantum yield less than 0.01%.However,the situation reverses with the addition of z... As one of the biological endogenous pigments,biliverdin(BV)and its dimethyl ester(BVE)have extremely weak uorescence in solution with quantum yield less than 0.01%.However,the situation reverses with the addition of zinc ions.The strength for uorescence of BVE-Zn^2+ complex is greatly enhanced and uorescence quantum yield can increase to5%.Herein,we studied ultrafast excited state dynamics of BVE-Zn^2+ complex in ethanol,npropanol,and DMSO solutions in order to reveal the mechanism of uorescence quantum yield enhancement.The results show that BVE can form a stable coordination complex with zinc with 1:1 stoichiometry in solution.BVE is structurally and energetically more stable in the complex.Using picosecond time-resolve uorescence and femtosecond transient absorption spectroscopy,we show that smaller non-radiative rate constant of BVE-Zn^2+ complex in DMSO is the key to increasing its uorescence quantum yield and the excited state decay mechanism is also revealed.These results provide valuable information about the uorescence property change after BVE binding to metal ions and may provide a guidance for the study of phytochromes or other uorescence proteins in which BV/BVE acts as chromophores. 展开更多
关键词 BILIVERDIN ZINC FLUORESCENCE Quantum yield Femtosecond transient absorption excited state dynamics
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Electron excitation from ground state to first excited state:Bohmian mechanics method
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作者 宋阳 赵双 +2 位作者 郭福明 杨玉军 李苏宇 《Chinese Physics B》 SCIE EI CAS CSCD 2016年第3期156-162,共7页
The excitation process of electrons from the ground state to the first excited state via the resonant laser pulse is investigated by the Bohmian mechanics method. It is found that the Bohmian particles far away from t... The excitation process of electrons from the ground state to the first excited state via the resonant laser pulse is investigated by the Bohmian mechanics method. It is found that the Bohmian particles far away from the nucleus are easier to be excited and are excited firstly, while the Bohmian particles in the ground state is subject to a strong quantum force at a certain moment, being excited, to the first excited state instantaneously. A detailed analysis for one of the trajectories is made, and finally we present the space and energy distribution of 2000 Bohmian particles at several typical instants and analyze their dynamical process at these moments. 展开更多
关键词 Bohmian mechanics excited state quantum force TRAJECTORY
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