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Time-dependent Density Functional-based Tight-bind Method Efficiently Implemented with OpenMP Parallel and GPU Acceleration

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Chinese Journal of Chemical Physics 2013年第6期26卷 635-645,I0003页

作者： guo-hong Fan Ke-li Han guo-zhong he State Key Laboratory of Molecular Reaction Dynamics Dalian Institute of Chemical Physics ChineseAcademy of Sciences Dalian 116023 China

The time-dependent density functional-based tight-bind （TD-DFTB） method is implemented on the multi-core and the graphical processing unit （GPU） system for excited state calcu-lations of large system with hundreds or thousands of atoms. Sparse matrix and OpenMP multithreaded are used for building the Hamiltonian matrix. The diagonal of the eigenvalue problem in the ground state is implemented on the GPUs with double precision. The GPU- based acceleration fully preserves all the properties, and a considerable total speedup of 8.73 can be achieved. A Krylov-space-based algorithm with the OpenMP parallel and CPU acceleration is used for finding the lowest eigenvalue and eigenvector of the large TDDFT matrix, which greatly reduces the iterations taken and the time spent on the excited states eigenvalue problem. The Krylov solver with the GPU acceleration of matrix-vector product can converge quickly to obtain the final result and a notable speed-up of 206 times can be observed for system size of 812 atoms. The calculations on serials of small and large systems show that the fast TD-DFTB code can obtain reasonable result with a much cheaper computational requirement compared with the first-principle results of CIS and full TDDFT calculation.

关键词： Density-functional theory Tight-binding method Time-dependent densityfunctional theory Excited state Graphical processing unit Krylov iterative algorithm Sparse matrix OpenMP

Time-dependent Wave Packet Quantum Scattering Study of Reaction S（3p）＋H2→HS＋H on a New ab initio Potential Energy Surface 3A’

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Chinese Journal of Chemical Physics 2012年第3期25卷 291-296,373页

作者： Shuang-jiang Lv Pei-yu Zhang guo-zhong he State Key Laboratory of Molecular Reaction Dynamics Dalian Institute of Chemical Physics ChineseAcademy of Sciences Dalian 115023 China

A new potential energy surface is presented for the triplet state 3At of the chemical reaction S（3P）＋H2 from a set of accurate ab initio data. The single point energies are computed using highly correlated complete active space self-consistent-field and multi-reference configuration interaction wave functions with a basis set of aug-cc-pV5Z. We have fitted the full set of energy values using many-body expansion method with an Aguado-Paniagua function. Based on the new potential energy surface, we carry out the time-dependent wave packet scattering calculations over the collision energy range of 0.8-2.2 eV. Both the centrifugalsudden approximation and Coriolis Coupling cross sections are obtained. In addition, the total reaction probabilities are calculated for the reactant H2 initially in the vibrational states v=0-3 （j=0）. It is found that initial vibrational excitation enhances the title reaction.

关键词： Potential energy surface Quantum-scattering Time-dependent wave packet

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BIOGRAPHY

Cell Research 1997年第1期 127-128页

作者： guo-zhong he Lun Xj Yan Yuan Chang

The　TheORY　OF　RESONANT　AND　NONRESONANT　PUMP－PROBE　POLARIZATIONSPECTROSCOPYFORGROUND－STATECOheRENCE

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Chinese Chemical Letters 1996年第4期7卷 353-356页

作者： Yi ZHAO guo zhong he(State Key Laboratory of Molecular Reaction Dynamics, Dalian Institute of Chemical Physics. Chinese Academy of Sciences, Dalian 116023) CHINESE ACAD SCI DALIAN INST CHEM PHYSSTATE KEY LAB MOL REACT DYNAMDALIAN 116023PEOPLES R CHINA

A density matrix treatment of the time evolution of the third order polarization response describing the ground state coherence induced by ultrafast pulses is given. The explicit formulas of polarization response for nonresonant and resonant excitation are derived. The results show that the signal can be greatly enhanced in case of resonance. For specification, we discuss the ground- state rotational coherence based on the if irreducible tensor algebra.

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Detection of OH Radical in the Photodissociation of p-Aminobenzoic Acid at 266 nm

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Chinese Journal of Chemical Physics 2009年第6期22卷 681-685,I0003页

作者： Can-hua Zhou Shi-bo Cheng Hong-ming Yin guo-zhong he State Key Laboratory of Molecular Reaction Dynamics Dalian Institute of Chemical Physics ChineseAcademy of Sciences Dalian 116023 China

Photodissociation of p-aminobenzoic acid at 266 nm was investigated by probing the nascent OH photoproduct employing the laser-induced fluorescence technique. It was found that the nascent OH radical was vibrationally cold and its rotational state distribution conformed to be a Boltzmann behavior, characterized by a rotational temperature of 1040±110 K. The rotational energy of OH was determined to be 8.78±0.84 kJ/mol. Between the two spinorbit states of OH, ^2Ⅱ3/2 and ^2Ⅱ1/2, the former was found to be preferentially populated. The distribution of the II（A＇） state for the A-doublet was dominant. Finally, a probable mechanism for the formation of OH produced from the photodissociation of p-aminobenzoic acid is discussed.

关键词： Photodissociation OH radical p-aminobenzoic acid Laser-induced fluorescence technique

Ab Initio Study of the Reaction: H + SO_2→HO + SO

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Chinese Chemical Letters 1998年第2期9卷 181-185页

作者： Rong Shun ZHU Jian Hua HUANG Ke Li HAN and guo zhong he(State Key Laboratory of Molecular Reaction Dynamics,Dalian Institute of Chemical Physics, Chinese Academy of Sciences, Dalian 116023) Chinese Acad Sci Dalian Inst Chem Phys State key Lab Mol React Dynam Dalian 116023 Peoples R China

The reaction of H+ SO2→HO + SO was theoretically investigated sing ab initio MOmethods, and HF/TZV (d, p) level of theory was employed to locate stationary points which werethen characterized by calculation of the vibrational frequencies. Energies were estimated at the optimized geometries using MP2/TZV (d, p) calculations. The results show that the caIculated geometries- frequencies. and thermochemical data were in good agreement with available experi-mental values. The IRC calculations confirmed that nonplanar HSO2 and HOSO adducts shouldbe more reasonable than those of planar conformation.

关键词： Hydrogen Sulfur dioxtde Reaction Ab initio calculation

Unexpected Chemistry from the Homogeneous Thermal Decomposition of Acetylene:An ab initio Study

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Chinese Journal of Chemical Physics 2018年第6期31卷 761-766,733页

作者： En-dong Wang Guang-yue Li Jun-xia Ding guo-zhong he State Key Laboratory of Molecular Reaction Dynamics Dalian Institute of Chemical Physics Chinese Academy of Science Dalian 116023 China University of the Chinese Academy of Sciences Beijing 100049 China College of Chemical Engineering North China University of Science and Technology Tangshan 063009 China

The formation of the aromatic ring during the formation of polycyclic aromatic hydrocarbons (PAHs) remains controversial and the experimental evidence is still lacking. Moreover, the formation mechanism of benzene from acetylene in the gas phase has also puzzled organic chemists for decades. here, ab initio molecular dynamics simulations and electronic structure calculations provide compelling evidence for an unexpected competitive reaction pathway in which the aromatic ring is formed through successive additions of vinylidene. Moreover, no collisions cause bond dissociation of the acetylene molecule during the formation of benzene in this work. This study reveals the key role for the vinylidene carbene and determines the lifetime of vinylidene.

关键词： ab initio calculations Acetylene Combustion Aromatic ring Carbenes

The TheORETICAL STUDIES OF PRODUCT ALIGNMENT OF The REACTIONS OF Na,F WITH CH_3I

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Chinese Chemical Letters 1993年第6期4卷 517-520页

作者： Ke Li HAN guo zhong he Nan Quan LOU State Key Laboratory of Molecular Reaction Dynamics,Dalian Institute of Chemical Physics,CAS,Dalian 116012,China

The NaI and IF product rotational alignment of the reactions of Na,F+CH_3I has been theoretically studied in a LEPS *** product alignment versus the relative translational energy of the reactants has been obtained.

关键词： Na The TheORETICAL STUDIES OF PRODUCT ALIGNMENT OF The REACTIONS OF Na,F WITH CH3I CH

The management of acetabular malunion with traumatic arthritis by total hip arthroplasty

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The management of acetabular malunion with traumatic arthrit...