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Investigation of isotope effects of dynamic properties for H(D) + OF reactions by the quasi-classical trajectory method

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Chinese Physics B 2010年第6期19卷 272-276页

作者：赵娟许燕孟庆田 College of Physics and Electronics Shandong Normal University

Quasi-classical trajectory （QCT） calculations are employed to study the dynamic properties for H（D）＋OF reactions on the adiabatic potential energy surface （PES） of the 1^3A″ triplet state. Obvious differences between the reaction probabilities for J=0, integral cross sections for J≠0, branch ratios of the product and internuclear distances as well as product rotational alignments between the title reactions axe found. These differences are attributed mainly to the different reduced masses of the reactants and the different zero-point energies （ZPEs） of the transition state.

关键词： isotope effects H(D)+OF reactions quasi-classical trajectory

Study of the isotope effects of Novel Superconducting LaH10-LaD10and H3S-D3S Systems

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Journal of High Energy Physics, Gravitation and Cosmology 2021年第4期7卷 1219-1229页

作者： Hassan H. Mohammed Department of Computer Technology Engineering Iraq University College Basrah Iraq

This paper is directed to study the isotope effects of some superconducting materials that have a strong coupling coefficient λ > 1.5, and focuses on new superconducting materials whose critical temperature is close to room temperature, specifically LaH10-LaD10 and H3S-D3S systems. The Eliashberg-McMillan (EM) model and the recent Gor’kov-Kresin (GK) model for evaluating the isotope effects coefficient α were examined for these systems. The predicted values of α as a function of pressure, as compared to experimental values led to inference that these two models, despite their importance and simplicity, cannot be considered complete. These models can be used to calculate isotope effect of most superconducting materials with strong coupling coefficients but with critical reliability. The significance of studying the isotope effect lies in the possibility of identifying the interatomic forces that control the properties of superconducting materials such as electrons-mediated phonons and Coulomb interactions.

关键词： isotope effects Superconductivity Strong Coupling Coefficient High Pressure

Quasi-classical trajectory study of the isotope effect on the stereodynamics in the reaction H(~2S) + CH(X^2Π;u= 0,j= 1) → C(~1D) + H_2(X^1Σ_g^+)

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Chinese Physics B 2014年第4期23卷 240-245页

作者：王允辉肖传云邓开明陆瑞锋 Department of Applied Physics Nanjing University of Science and Technology

The isotope effect on the stereodynamic properties in the title reaction is investigated by a quasi-classical trajectory （QCT） method on the 11At potential energy surface at a collision energy of 23.06 kcal/mol. The angular distributions P（φr ）, P（θr）, P（θr, φr）, and the polarization-dependent generalized differential cross sections are calculated, which demonstrate the observable influences on the rotational polarization of the product by the isotopic substitution of H with D.

关键词： quasi-classical trajectory stereodynamics isotope effects product polarization

Roaming Dynamics of H+C_(2)D_(2) Reaction on Fundamental-Invariant Neural Network Potential Energy Surface

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Chinese Journal of Chemical Physics 2022年第2期35卷 295-302,I0002页

作者： Yuyao Bai Yan-Lin Fu Yong-Chang Han Bina Fu Dong HZhang State Key Laboratory of Molecular Reaction Dynamics and Center for Theoretical and Computational Chemistry Dalian Institute of Chemical PhysicsChinese Academy of SciencesDalian 116023China School of Physics Dalian University of TechnologyDalian 116024China

We performed extensive quasiclassical trajectory calculations for the H+C_(2)D_(2)→HD+C_(2)D/D_(2)+C_(2)H reaction based on a recently developed,global and accurate potential energy surface by the fundamental-invariant neural network *** direct abstraction pathway plays a minor role in the overall reactivity,which can be negligible as compared with the roaming *** acetylenefacilitated roaming pathway dominates the reactivity,with very small contributions from the vinylidene-facilitated *** the roaming pathways proceed via the short-lived or long-lived complex forming process,the computed branching ratio of product HD to D_(2) is not far away from 2:1,implying roaming dynamics for this reaction is mainly contributed from the long-lived complex-forming *** resulting angular distributions for the two product channels are also quite *** computational results give valuable insights into the significance and isotope effects of roaming dynamics in the biomolecular reactions.

关键词： Roaming dynamics Acetylene Vinylidene isotope effects

Theoretical study of the radiative decay processes in H^+(D^+,T^+)–Be collisions

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Chinese Physics B 2018年第12期27卷 217-223页

作者： Huilin Wei Xiaojun Liu Beijing Sport University Beijing 100084China Department of Physics College of ScienceQiqihar UniversityQiqihar 161006China

The potential energy curves of X~1Σ~+, A~1Σ~+, C~1Σ~+, and B~1Π are calculated with high-level MRDCI method, and the calculated spectroscopic constants of those states are in good agreement with most recent experimental data. On the basis of high precision PECs, the radiative processes of H~++ Be collisions are studied by using the fully quantum, optical potential and semiclassical methods in the energy ranges of 10-8eV/u–0.1 eV/u, and the radiative decay, the radiative charge transfer,and the radiative association cross-sections are computed. It is found that the radiative association process is dominant in the energy region of 10-8eV/u–0.02 eV/u, while radiative charge transfer becomes important at higher energies. Rich resonance structures are present in the radiative association and charge transfer cross-sections in the whole energy region considered, which result from the interaction between the quasi-bound rovibrational(J, v) states in the entrance channel with the final continuum state. Significant isotope effects have been found in the radiative decay processes of H~++ Be collisions.

关键词： optical-potential method radiative charge transfer radiative association radiative decay isotope effects

Review of Feynman’s Path Integral in Quantum Statistics:from the Molecular Schrödinger Equation to Kleinert’s Variational Perturbation Theory

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Communications in Computational Physics 2014年第4期15卷 853-894页

作者： Kin-Yiu Wong Department of Physics High Performance Cluster Computing CentreInstitute of Computational and Theoretical StudiesHong Kong Baptist University224 Waterloo RoadKowloon TongHong Kong Institute of Research and Continuing Education Hong Kong Baptist University(Shenzhen)

Feynman’s path integral reformulates the quantum Schrödinger differential equation to be an integral *** has been being widely used to compute internuclear quantum-statistical effects on many-body molecular *** this Review,the molecular Schrödinger equation will first be introduced,together with the BornOppenheimer approximation that decouples electronic and internuclear *** effective semiclassical potentials,e.g.,centroid potential,which are all formulated in terms of Feynman’s path integral,will be discussed and *** semiclassical potentials can be used to directly calculate the quantum canonical partition function without individual Schrödinger’s energy *** a result,path integrations are conventionally performed with Monte Carlo and molecular dynamics sampling *** complement these techniques,we will examine how Kleinert’s variational perturbation(KP)theory can provide a complete theoretical foundation for developing non-sampling/non-stochastic methods to systematically calculate centroid *** enable the powerful KP theory to be practical for many-body molecular systems,we have proposed a new path-integral method:automated integrationfree path-integral(AIF-PI)*** to the integration-free and computationally inexpensive characteristics of our AIF-PI method,we have used it to perform ab initio path-integral calculations of kinetic isotope effects on proton-transfer and RNA-related phosphoryl-transfer chemical *** computational procedure of using our AIF-PI method,along with the features of our new centroid path-integral theory at the minimum of the absolute-zero energy(AMAZE),are also highlighted in this review.

关键词： Feynman’s path integral Kleinert’s variational perturbation theory Schrödinger’s equation quantum statistics centroid potential energy quantum tunneling zero-point energy isotope effects