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Dynamics of the Au+H2 reaction by time-dependent wave packet and quasi-classical trajectory methods
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作者 Yong Zhang Chengguo Jiang 《Chinese Physics B》 SCIE EI CAS CSCD 2019年第12期142-147,共6页
Dynamics of the Au + H2 reaction are studied using time-dependent wave packet(TDWP) and quasi-classical trajectory(QCT) methods based on a new potential energy surface [Int. J. Quantum Chem. 118 e25493(2018)]. The dyn... Dynamics of the Au + H2 reaction are studied using time-dependent wave packet(TDWP) and quasi-classical trajectory(QCT) methods based on a new potential energy surface [Int. J. Quantum Chem. 118 e25493(2018)]. The dynamic properties such as reaction probability, integral cross section, differential cross section and the distribution of product are studied at state-to-state level of theory. Furthermore, the present results are compared with the theoretical studies available.The results indicate that the complex-forming reaction mechanism is dominated in the reaction in the low collision energy region and the abstract reaction mechanism plays a dominant role at high collision energies. Different from previous theoretical calculations, the side-ways scattering signals are found in the present work and become more and more apparent with increasing collision energy. 展开更多
关键词 reaction probability integral cross section time-dependent wave packet quasi-classical trajectory
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Time-dependent approach to the double-channel dissociation of the NaCs molecule induced by pulsed lasers 被引量:2
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作者 张彩霞 牛余全 孟庆田 《Chinese Physics B》 SCIE EI CAS CSCD 2014年第10期96-102,共7页
The dynamics of the double-channel dissociation of the NaCs molecule is investigated by using the time-dependent wave packet (TDWP) method with the "split operator-Fourier transform" scheme. At a given wavelength ... The dynamics of the double-channel dissociation of the NaCs molecule is investigated by using the time-dependent wave packet (TDWP) method with the "split operator-Fourier transform" scheme. At a given wavelength and intensity of laser pulse, the population of each state changing with time is obtained. The photo-absorption spectra and kinetic- energy distribution of the dissociation fragments, which exhibit vibration-level structure and dispersion of the wave packet, respectively, are also obtained. The results show that by increasing the laser intensity, one can find not only the band center shift of the photo-absorption spectrum, but also the change of the fragment energy. The appearance of the diffusive band in the photo-absorption spectrum and the multiple peaks in the kinetic-energy spectrum can be attributed to the effects of the predissoeiation limit and the external field. 展开更多
关键词 time-dependent wave packet method photo-dissociation dynamics photo-absorption spectrum kinetic-energy spectrum NaCs
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Time-dependent theoretical approach to the influence of laser fields on the resonance enhanced multi-photon ionization of SH radical
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作者 岳大光 郑晓云 +2 位作者 刘浩 王春兴 孟庆田 《Chinese Physics B》 SCIE EI CAS CSCD 2009年第4期1479-1485,共7页
This paper reports that the (2+1) resonance enhanced multi-photon ionization spectra of SH radical in external fields are simulated using the split-operator scheme of time-dependent wave-packet method. Two ionic st... This paper reports that the (2+1) resonance enhanced multi-photon ionization spectra of SH radical in external fields are simulated using the split-operator scheme of time-dependent wave-packet method. Two ionic states, i.e. a1△ and b1∑+, are involved in the simulation. It gives the simulated photoelectron spectra, the population in each electronic state, as well as the projection of the wave-packet in each electronic state on different vibrational states. These results show that the so-called four-state model can represent the experimental results well. 展开更多
关键词 photoelectron spectra time-dependent wave-packet method four-state model multiphoton ionization
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Influence of laser fields on the vibrational population of molecules and its wave-packet dynamical investigation 被引量:4
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作者 王军 刘芳 +4 位作者 岳大光 赵娟 许燕 孟庆田 Liu Wing-Ki 《Chinese Physics B》 SCIE EI CAS CSCD 2010年第12期193-202,共10页
The time-dependent wave packet method is used to investigate the influence of laser-fields on the vibrational population of molecules. For a two-state system in laser fields, the populations on different vibrational l... The time-dependent wave packet method is used to investigate the influence of laser-fields on the vibrational population of molecules. For a two-state system in laser fields, the populations on different vibrational levels of the upper and lower electronic states are given by wavefunctions obtained by solving the Schrbdinger equation with the split- operator method. The calculation shows that the field parameters, such as intensity, wavelength, duration, and delay time etc. can have different influences on the vibrational population. By varying the laser parameters appropriately one can control the evolution of wave packet and so the vibrational population in each state, which will benefit the light manipulation of atomic and molecular processes. 展开更多
关键词 intense laser field time-dependent wave packet method light-matter interaction vibrational population
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Study on wave packet dynamics of E^1Σ_g^+ state of Li_2 with femtosecond-resolved photoelectron spectra 被引量:1
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作者 刘玉芳 刘瑞琼 丁俊霞 《Chinese Physics B》 SCIE EI CAS CSCD 2010年第3期269-273,共5页
Wave packet dynamics of the Li2 molecule are investigated by using the time-dependent quantum wave packet method, and the time-resolved photoelectron spectra of the Li2 molecule are calculated. The time-resolved wave ... Wave packet dynamics of the Li2 molecule are investigated by using the time-dependent quantum wave packet method, and the time-resolved photoelectron spectra of the Li2 molecule are calculated. The time-resolved wave packet theory is used to reasonably interpret the phenomena of the photoelectron spectra for different parameters. Our calculation shows that the loss of the wave packets in the shelf state area of E1∑g+ plays a prominent role in the process of photoionization with the increase of the delay time. Moreover, the oscillation of the wave packet on the E1∑g+ curve symbolizes a decreasing process of energy. 展开更多
关键词 time-dependent wave packet photoelectron spectra PUMP-PROBE
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Magnetic Field Induction and Time Intervals of the Electron Transitions Approached in a Classical and Quantum-Mechanical Way
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作者 Stanislaw Olszewski 《Journal of Modern Physics》 2011年第11期1305-1309,共5页
The motion of electron wave packets of a metal is examined classically in the presence of the magnetic field with the aim to calculate the time intervals between two states lying on the same Fermi surface. A lower lim... The motion of electron wave packets of a metal is examined classically in the presence of the magnetic field with the aim to calculate the time intervals between two states lying on the same Fermi surface. A lower limiting value of the transition time equal to about 10–18 sec is estimated as an average for the case when the states are lying on the Fermi surface having a spherical shape. Simultaneously, an upper limit for the electron circular frequency in a metal has been also derived. A formal reference of the classical transition time to the time interval entering the energy-time uncertainty relations known in quantum mechanics is obtained. 展开更多
关键词 Lorentz Force and Magnetic Induction Electron wave packets Changes of the Electron Momentum Transition time between quantum States
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Quantum dynamics of dissociative adsorption of H_2 and D_2:The time-dependent wave packet method
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作者 关大任 华东明 +1 位作者 张庆刚 丁世良 《Science China Chemistry》 SCIE EI CAS 1998年第4期403-409,共7页
A time dependent quantum wave packet method was used to study the dynamics of dissociative adsorption of H 2 and D 2 on a flat and static surface. The molecule surface interaction is described using a modified London ... A time dependent quantum wave packet method was used to study the dynamics of dissociative adsorption of H 2 and D 2 on a flat and static surface. The molecule surface interaction is described using a modified London Eyring Polanyi Sato (LEPS) type potential for the H 2/Ni(100) system. The three dimensional (3 D) dissociation probabilities were calculated for different initial rovibrational states as a function of initial incident energies. Our results show that the dissociation of the diatomic rotational states whose quantum numbers satisfy j+m =odd is forbidden at low energies for the homonuclear H 2 and D 2 due to the selection rule. The effect of the rotational orientation of diatoms on adsorption predicts that the in plane rotation (m=j) is more favorable for dissociation than the out of plane rotation (m=0) . Enhanced dissociation for vibrationally excited molecules and the significant enhancement of the dissociation probability of H 2 when compared to D 2 were explained reasonably in terms of quantum mechanical zero point energies, the tunneling effect and the reflection from an activation barrier. 展开更多
关键词 time dependent wave packet method dissociative ADSORPTION quantum DYNAMICS optical potential.
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Three-dimensional quantum dynamics study of vibrational predissociation of HeI_2 van der Waals molecule for low vibrational excitation using the time-dependent wave packet method
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作者 关大任 赵显 +1 位作者 邓从豪 John Z.H.Zhang 《Science China Chemistry》 SCIE EI CAS 1997年第4期442-448,共7页
Three-dimensional quantum mechanical calculations for vibrational predissociation of HeI2(B) van der Waals molecules are presented using the time-dependent wave packet technique within the golden rule approxima tion.T... Three-dimensional quantum mechanical calculations for vibrational predissociation of HeI2(B) van der Waals molecules are presented using the time-dependent wave packet technique within the golden rule approxima tion.The total and partial decay widths,lifetimes,rates and their dependence on initial vibrational states were obtained for HeI2 at low initial vibrational excited levels.Our calculations show that the calculated tota decay widths,lifetimes and rates agree well with those extrapolated from experimental data available The predicted total decay widths as a function of initial vibrational states exhibit highly nonlinear behavior.The very short propagation time (less.than 1 ps) required in the golden rule wave packet calculation is determined by the duration time of the final state inter-action between the fragments on the vibrationally deexcited adiabatic potential surface.The final state interaction between the fragments is shown to play an important role in determining the final rotational distribution This interpreta tion clearly explains the dynamical effect that the final rotational distribution shifts to the lower rotational energy levels as the initial vibrational quantum number v increases. 展开更多
关键词 time-dependent GOLDEN rule wave packet approach VIBRATIONAL PREDISSOCIATION HeI2 van der Waats MOLECULE decay WIDTHS final rotational distribution
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Theoretical study of the influence of intense femtosecond laser field on the evolution of the wave packet and the population of NaRb molecule 被引量:5
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作者 马宁 王美山 +2 位作者 杨传路 马晓光 王德华 《Chinese Physics B》 SCIE EI CAS CSCD 2010年第2期213-218,共6页
Employing the two-state model and the time-dependent wave packet method, we have investigated the influences of the parameters of the intense femtosecond laser field on the evolution of the wave packet, as well as the... Employing the two-state model and the time-dependent wave packet method, we have investigated the influences of the parameters of the intense femtosecond laser field on the evolution of the wave packet, as well as the population of ground and double-minimum electronic states of the NaRb molecule. For the different laser wavelengths, the evolution of the wave packet of 6{ }^1/Sigma ^ + state with time and internuclear distance is different, and the different laser intensity brings different influences on the population of the electronic states of the NaRb molecule. One can control the evolutions of wave packet and the population in each state by varying the laser parameters appropriately, which will be a benefit for the light manipulation of atomic and molecular processes. 展开更多
关键词 intense femtosecond laser field time-dependent wave packet method wave packet POPULATION
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Manifestation of external field effect in time-resolved photo-dissociation dynamics of LiF 被引量:1
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作者 孟庆田 A. J. C. Varandas 《Chinese Physics B》 SCIE EI CAS CSCD 2013年第7期140-147,共8页
The photo-dissociation dynamics of LiF is investigated with newly constructed accurate ab initio potential energy curves (PECs) using the time-dependent quantum wave packet method. The oscillations and decay of the ... The photo-dissociation dynamics of LiF is investigated with newly constructed accurate ab initio potential energy curves (PECs) using the time-dependent quantum wave packet method. The oscillations and decay of the wave packet on the adiabats as a function of time are given, which can be compared with the femtosecond transition-state (FTS) spectroscopy. The photo-absorption spectra and the kinetic-energy distribution of the dissociation fragments, which can exhibit the vibration-level structure and the dispersion of the wave packet, respectively, are also obtained. The investigation shows a blue shift of the band center for the photo-absorption spectrum and multiple peaks in the kinetic-energy spectrum with increasing laser intensity, which can be attributed to external field effects. By analyzing the oscillations of the wave packet evolving on the upper adiabat, an approximate inversion scheme is devised to roughly deduce its shape. 展开更多
关键词 photo-dissociation dynamics time-dependent wave packet method photo-absorption spectra external field effect
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Alternative Approach to Time Evaluation of Schrodinger Wave Functions 被引量:1
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作者 Mustafa Erol 《Journal of Modern Physics》 2012年第11期1716-1721,共6页
Time evaluation of wave functions for any quantum mechanical system/particle is essential nevertheless quantum mechanical counterpart of the time dependant classical wave equation does simply not appear. Epistemologic... Time evaluation of wave functions for any quantum mechanical system/particle is essential nevertheless quantum mechanical counterpart of the time dependant classical wave equation does simply not appear. Epistemologically and ontologically considered time dependant momentum operator is initially defined and an Alternative Time Dependant Schrodinger Wave Equation (ATDSWE) is plainly derived. Consequent equation is primarily solved for the free particles, in a closed system, signifying a good agreement with the outcomes of the ordinary TDSWE. Free particle solution interestingly goes further possibly tracing some signs of new pathways to resolve the mysterious quantum world. 展开更多
关键词 time dependant Schrodinger wave Equation wave Function Evolution quantum Theory quantum Philosophy
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Reaction mechanism of D + ND→N + D_2 and its state-to-state quantum dynamics
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作者 Ting Xu Juan Zhao +1 位作者 Xian-Long Wang Qing-Tian Meng 《Chinese Physics B》 SCIE EI CAS CSCD 2019年第2期173-178,共6页
The quantum state-to-state calculations of the D + ND→N + D_2 reaction are performed on a potential energy surface of 4 A'' state. The state-resolved integral and differential cross sections and product state... The quantum state-to-state calculations of the D + ND→N + D_2 reaction are performed on a potential energy surface of 4 A'' state. The state-resolved integral and differential cross sections and product state distributions are calculated and discussed. It is found that the rotational distribution, rather than the vibrational distribution, of the product has an obvious inversion. Due to the fact that it is a small-impact-parameter collision, its product D_2 is mainly dominated by rebound mechanism, which can lead to backward scattering at low collision energy. As the collision energy increases, the forward scattering and sideward scattering begin to appear. In addition, the backward collision is also found to happen at high collision energy, through which we can know that both the rebound mechanism and stripping mechanism exist at high collision energy. 展开更多
关键词 state-to-state quantum dynamics time-dependent wave packet D+ND differential cross section
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State-to-state quantum dynamics of the N(~4S)+H_2(X^1Σ^+) → NH(X^3Σ^-)+H(~2S) reaction and its reaction mechanism analysis
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作者 张静 高守宝 +1 位作者 吴慧 孟庆田 《Chinese Physics B》 SCIE EI CAS CSCD 2015年第8期279-285,共7页
Quantum state-to-state dynamics of the N(4S) + H-2(X1+Σ) → NH(X3Σ) + H(2S) reaction is reported in an accurate novel potential energy surface constructed by Zhai et al.(2011 J. Chem. Phys. 135 104314). The time-dep... Quantum state-to-state dynamics of the N(4S) + H-2(X1+Σ) → NH(X3Σ) + H(2S) reaction is reported in an accurate novel potential energy surface constructed by Zhai et al.(2011 J. Chem. Phys. 135 104314). The time-dependent wave packet method, which is implemented on graphics processing units, is used to calculate the differential cross sections. The influences of the collision energy on the product state-resolved integral cross sections and total differential cross sections are calculated and discussed. It is found that the products NH are predominated by the backward scattering due to the small impact parameter collisions, with only minor components being forward and sideways scattered, and have an inverted rotational distribution and no inversion in vibrational distributions; both rebound and stripping mechanisms exist in the case of high collision energies. 展开更多
关键词 state-to-state quantum dynamics time-dependent wave packet differential cross section N(4S) + H2
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Time-dependent wave packet approach to the pulse delay effect upon RbI photoelectron spectrum
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作者 LIU Chunhua MENG Qingtian ZHANG Qinggang 《Science China Chemistry》 SCIE EI CAS 2006年第3期214-218,共5页
The time-resolved photoelectron spectrum (TRPES) of Rbl molecule is simulatedusing the time-dependent wave-packet method. Both the normal three-photon ionization process andauto-ionization process are involved in the ... The time-resolved photoelectron spectrum (TRPES) of Rbl molecule is simulatedusing the time-dependent wave-packet method. Both the normal three-photon ionization process andauto-ionization process are involved in the simulation. The calculated results show that the changeof delay time will influence the shape of the photoelectron spectrum (PES), and the influence issubstantially due to the existence of the crossing between excited states and the strong laser fieldwhich will change the position of relevant curves. 展开更多
关键词 time-dependent wave packet method MULTIPHOTON IONIZATION (MPI) time-RESOLVED PHOTOELECTRON spectrum (TRPES) auto-ionization.
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Non-adiabatic quantum dynamical studies of Na(3p) + HD(v = 1, j5) = 0)→NaH/NaD + D/H reaction
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作者 Yue-Pei Wen Bayaer Buren Mao-Du Chen 《Chinese Physics B》 SCIE EI CAS CSCD 2019年第6期169-175,共7页
Non-adiabatic dynamical calculations are carried out for the Na(3 p)+HD(ν = 1, j = 0)→NaH/NaD+D/H reaction on the diabatic potential energy surfaces of Wang et al.(Sci. Rep. 2018, 8, 17960) by using the time-depende... Non-adiabatic dynamical calculations are carried out for the Na(3 p)+HD(ν = 1, j = 0)→NaH/NaD+D/H reaction on the diabatic potential energy surfaces of Wang et al.(Sci. Rep. 2018, 8, 17960) by using the time-dependent wave packet method. The state-to-state integral cross sections and differential cross sections of two reaction channels(NaH/NaD+D/H)are calculated for collision energy up to 0.4 eV. The cross section branching ratio indicates that the dominant reaction channel changes from NaD+H to NaH+D when the collision energy is larger than 0.227 eV. The products from two reaction channels both prefer to form in vibrationally cold but rotationally hot states, and they both tend to forward scattering. 展开更多
关键词 time-dependent wave packet method NON-ADIABATIC REACTION integral CROSS SECTION differential CROSS SECTION
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State-to-state quantum dynamics of N(2D) + HD (v =0, j = 0) reaction
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作者 张勇 《Chinese Physics B》 SCIE EI CAS CSCD 2016年第12期228-234,共7页
The N(2D) + HD (v = 0, j = 0) reaction has been studied by a quantum time-dependent wave packet approach with a second-order split operator on the potential energy surface of Li et al. (Li Y, Yuan J, Chen M, Ma ... The N(2D) + HD (v = 0, j = 0) reaction has been studied by a quantum time-dependent wave packet approach with a second-order split operator on the potential energy surface of Li et al. (Li Y, Yuan J, Chen M, Ma F and Sun M J. Comput. Chem. 34 1686). The rovibrationally resolved reaction probability, vibrationally integral cross section, and differential cross section of the NH + D and ND + H channel are investigated at the state-to-state level of theory. The experimental data of the thermal rate constant of two output channels is very scare, but the sum of the two output channels is in excellent agreement with the experimental data which was reported by Umemoto et al. It may imply that the thermal rate constants of the two output channels are accurate and reliable. 展开更多
关键词 N(2D) HD time-dependent wave packet differential cross section thermal rate constant
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Mechanism analysis of reaction S+(2D)+H2(X1Σg^+) → SH+(X3Σ-) + H(2S) based on the quantum state-to-state dynamics
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作者 Jin-Yu Zhang Ting Xu +3 位作者 Zhi-Wei Ge Juan Zhao Shou-Bao Gao Qing-Tian Meng 《Chinese Physics B》 SCIE EI CAS CSCD 2020年第6期146-152,共7页
We present a state-to-state dynamical calculation on the reaction S++ H2→ SH+ +H based on an accurate X2 A″ potential surface. Some reaction properties, such as reaction probability, integral cross sections, product... We present a state-to-state dynamical calculation on the reaction S++ H2→ SH+ +H based on an accurate X2 A″ potential surface. Some reaction properties, such as reaction probability, integral cross sections, product distribution, etc.,are found to be those with characteristics of an indirect reaction. The oscillating structures appearing in reaction probability versus collision energy are considered to be the consequence of the deep potential well in the reaction. The comparison of the present total integral cross sections with the previous quasi-classical trajectory results shows that the quantum effect is more important at low collision energies. In addition, the quantum number inversion in the rotational distribution of the product is regarded as the result of the heavy–light–light mass combination, which is not effective for the vibrational excitation. For the collision energies considered, the product differential cross sections of the title reaction are mainly concentrated in the forward and backward regions, which suggests that there is a long-life intermediate complex in the reaction process. 展开更多
关键词 state-to-state reaction dynamics time-dependent wave packet S++H2 differential and integral cross sections
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De Broglie’s Velocity of Transition between Quantum Levels and the Quantum of the Magnetic Spin Moment Obtained from the Uncertainty Principle for Energy and Time
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作者 Stanislaw Olszewski 《Journal of Modern Physics》 2014年第18期2022-2029,共8页
The De Broglie’s approach to the quantum theory, when combined with the conservation rule of momentum, allows one to calculate the velocity of the electron transition from a quantum state n to its neighbouring state ... The De Broglie’s approach to the quantum theory, when combined with the conservation rule of momentum, allows one to calculate the velocity of the electron transition from a quantum state n to its neighbouring state as a function of n. The paper shows, for the case of the harmonic oscillator taken as an example, that the De Broglie’s dependence of the transition velocity on n is equal to the n-dependence of that velocity calculated with the aid of the uncertainty principle for the energy and time. In the next step the minimal distance parameter provided by the uncertainty principle is applied in calculating the magnetic moment of the electron which effectuates its orbital motion in the magnetic field. This application gives readily the electron spin magnetic moment as well as the quantum of the magnetic flux known in superconductors as its result. 展开更多
关键词 Velocity of the Electron Transitions between quantum Levels De Broglie wave packets Magnetic Moment of the Electron Spin quantum of the Magnetic Flux The Uncertainty Principle for Energy and time
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OH+HCl→Cl+H_(2)O反应中的反应物转动激发效应
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作者 徐昕 陈俊 +1 位作者 刘舒 张东辉 《Chinese Journal of Chemical Physics》 SCIE EI CAS CSCD 2024年第2期211-220,I0102,共11页
本文在最近构建的F12a势能面上,对OH+HCl→Cl+H_(2)O的一系列反应物转动激发态进行了势能平均的五维含时波包计算,得到了初始态选择的反应几率和速率常数。研究发现,除了很低碰撞能量,单独激发反应物HCl到j_(1)=2或者OH到j_(2)=1得到了... 本文在最近构建的F12a势能面上,对OH+HCl→Cl+H_(2)O的一系列反应物转动激发态进行了势能平均的五维含时波包计算,得到了初始态选择的反应几率和速率常数。研究发现,除了很低碰撞能量,单独激发反应物HCl到j_(1)=2或者OH到j_(2)=1得到了总反应几率的最大值.在低能区域,随着OH转动激发的增加,反应几率的共振增强迅速减小,导致250K以下的速率常数迅速下降HCl和OH同时转动激发的速率常数不是单独激发结果的简单叠加。最后,通过对(5,5)态以下初始转动态的速率常数进行玻尔兹曼平均,得到了反应的热速率常数,与实验结果基本吻合。 展开更多
关键词 反应物转动激发 含时波包 反应几率 FESHBACH共振 速率常数
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含时紧束缚模型中的波包动力学
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作者 王羽婷 张禧征 《天津师范大学学报(自然科学版)》 CAS 北大核心 2024年第1期34-41,55,共9页
为了发展与构建新的量子调控方法与机制,基于含时磁通作用的一维紧束缚环体系,通过计算系统的能谱和传播子,研究了含时外场下单粒子波包的动力学行为.结果表明:矢势可以以相位的形式出现在紧束缚模型的二次量子化哈密顿量中,且其含时变... 为了发展与构建新的量子调控方法与机制,基于含时磁通作用的一维紧束缚环体系,通过计算系统的能谱和传播子,研究了含时外场下单粒子波包的动力学行为.结果表明:矢势可以以相位的形式出现在紧束缚模型的二次量子化哈密顿量中,且其含时变化所诱导的波包动力学效应与存在外电场时系统的动力学效应相同,表现为与经典物理中的法拉第电磁感应定律一致,这种与经典物理相对应的关系为人们构建新的量子调控机制提供了重要的指导思想. 展开更多
关键词 量子控制 含时紧束缚 波包 半经典近似 动力学
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