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Theoretical studies on the potential energy surfaces and vibrational energy levels of HXeF and HXeCl

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Science China Chemistry 2007年第1期50卷 7-10页

作者： HUANG ZhengGuo xie daiqian ZHU Hua Laboratory of Mesoscopic Chemistry Institute of Theoretical and Computational ChemistrySchool of Chemistry and Chemical EngineeringNanjing UniversityNanjing 210093China Department of Chemistry Sichuan UniversityChengdu 610064China

The potential energy surfaces for the electronic ground state of the HXeCl and HXeF molecules are constructed by using the internally contracted multi-reference configuration interaction with the Davidson correction (icMRCl+Q) method and large basis sets. The stabilities and dissociation barriers are identified from the potential energy surfaces. The three-body dissociation channel is found to be the dominate dissociation channel for HXeCl, while two dissociation channels are possible and competitive for HXeF. Based on the obtained potentials, vibrational energy levels of HXeCl and HXeF are calculated using the Lanczos algorithm. Our theoretical results are in good agreement with the available observed values. Particularly, the calculated fundamental frequency of the H—Xe stretching vibration including the Xe matrix effect of HXeCl is found to be 1666.6 cm?1, which is only 17.6 cm?1 higher than the recently observed value of 1649 cm?1.

关键词： HXeF HXeCl vibrational energy level potential energy surface

Theoretical study of adsorption and dissociation of NH_3 on the Ir{110}(1×2) surface

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Chinese Science Bulletin 2008年第20期53卷 3169-3172页

作者： HUANG WuYing xie daiqian Key Laboratory of Mesoscopic Chemistry Institute of Theoretical and Computational Chemistry School of Chemistry and Chemical Engineering Nanjing University Nanjing 210093 China

The adsorption and dissociation of NH3 on Ir{110}(1×2) have been investigated using the densityfunctional calculations at a coverage of 0.25 ML. The adsorption sites, energy, and geometries were obtained for NH3, NH2, and H adsorptions on the surface. The transition state for NH3 dissociation on Ir{110}(1×2) was also identified. It was found that NH3 is adsorbed preferentially at the ridge atop site, while NH2 and H are adsorbed at the ridge bridge site. The activation barrier of NH3 dissociation is 78.4 kJ/mol, which is very close to the NH3 adsorption energy of 90.0 kJ/mol. This indicates that the desorption and dissociation of NH3 on Ir{110}(1×2) are very competitive, which is consistent with the recent experimental results.

关键词：氨气铱吸附分裂密度泛函理论跃迁态

Density functional theory study of proton transfer in carbonic anhydrase

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Chinese Science Bulletin 2005年第22期50卷 2557-2559页

作者： ZHANG Lidong xie daiqian Department of Chemistry Institute of Theoretical and Computational Chemistry Laboratory of Mesoscopic Chemistry Nanjing UniversityNanjing 210093 China

Proton transfer in carbonic anhydrase II has been studied at the B3LYP/6-31G(D) level. The active site model consists of the zinc ion, four histidine residues, two threonine residues, and three water molecules. Our calcula- tions showed that the proton of the zinc-bound water mole- cule could be transferred to the nearest water molecule and an intermediate containing H3O+ is then formed. The inter- mediate is only 1.3 kJ·mol-1 above the reactant complex, whereas the barrier height for the proton transfer is about 8.1 kJ·mol?1.

关键词：质子传输密度函数反应装置 CA 可逆水合作用化学反应

The microscopic formation mechanism of O+H_(2) products from photodissociation of H_(2)O

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Chinese Journal of Structural Chemistry 2024年第5期43卷 11-13页

作者： Yubang Li Xixi Hu daiqian xie Kuang Yaming Honors School Jiangsu Key Laboratory of Vehicle Emissions ControlNanjing UniversityNanjing210023China Institute of Theoretical and Computational Chemistry Key Laboratory of Mesoscopic ChemistrySchool of Chemistry and Chemical EngineeringNanjing UniversityNanjing210023China

Photodissociation dynamics of water involving its B electronic states yielding OH(A^(2)Σ+/X^(2)Π)+H(^(2)S)products has been intensively investi-gated by both experimental and theoretical studies[1].Theoretically,the Dobbyn-Knowles potential energy surfaces(DK PESs)[2]based on limited complete active space self-consistent field(CASSCF)points were used in dynamic studies for water photodissociation and O+H_(2)reaction about 20 years ago,but the accuracy is not enough to meet current re-quirements.

关键词： mechanism enough yielding

Dynamical resonance in F+H_2 chemical reaction and rotational excitation effect

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Chinese Science Bulletin 2007年第8期52卷 1009-1012页

作者： YANG XueMing xie daiqian ZHANG DongHui State Key Laboratory of Molecular Reaction Dynamics Dalian Institute of Chemical Physics Chinese Academy of Sciences Dalian 116023 China Institute of Theoretical and Computational Chemistry College of Chemistry and Chemical Engineering Nanjing University Nanjing 210093 China

Reaction resonance is a frontier topic in chemical dynamics research,and it is also essential to the understanding of mechanisms of elementary chemical *** short article describes an im- portant development in the frontier of *** evidence of reaction resonance has been detected in a full quantum state resolved reactive scattering study of the F+H2 *** accurate full quantum scattering theoretical modeling shows that the reaction resonance is caused by two Feshbach resonance *** studies show that quantum interference is present between the two resonance states for the forward scattering *** study is a significant step forward in our understanding of chemical reaction resonance in the benchmark F+H2 *** experimental studies on the effect of H2 rotational excitation on dynamical resonance have been carried ***- namical resonance in the F+H2(j=1)reaction has also been observed.

关键词：反应动力学反应共振化学反应转动激发效应

Theoretical prediction of the noble gas complexes HeAuF and NeAuF

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Science China Chemistry 2009年第11期52卷 1987-1990页

作者： CHEN Rong ZHU Hua xie daiqian YAN GuoSen School of Chemistry Sichuan UniversityChengdu 610064China State Key Laboratory of Biotherapy Sichuan UniversityChengdu 610064China Institute of Theoretical and Computational Chemistry Key Laboratory of Mesoscopic ChemistrySchool of Chemistry and Chemical EngineeringNanjing UniversityNanjing 210093China

Ab initio calculations were carried out to investigate the structures and the stability of the noble gas complexes HeAuF and NeAuF through MP2 and CCSD(T) *** HeAuF was predicted to have a linear structure with weak He-Au covalent bonding,the distance of which is closer to the covalent limit in comparison with the corresponding van der Waals *** dissociation energy with respect to He + AuF was found to be 24 and 26 kJ·mol-1 at the CCSD(T)/basis set B and B' levels,***,similar calculations for NeAuF indicate that NeAuF is not a stable species.

关键词： HeAuF NeAuF structure stability

Full-Dimensional Potential Energy Surfaces of Ground(X^(2)A′)and Excited(A^(2)A″)Electronic States of HCO and Absorption Spectrum

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Chinese Journal of Chemical Physics 2022年第2期35卷 303-310,I0002页

作者： Qixin Chen Shanyu Han Xixi Hu daiqian xie Institute of Theoretical and Computational Chemistry Key Laboratory of Mesoscopic ChemistrySchool of Chemistry and Chemical EngineeringNanjing UniversityNanjing 210023China Department of Chemistry and Chemical Biology University of New MexicoNew Mexico 87131USA Kuang Yaming Honors School Institute for Brain SciencesNanjing UniversityNanjing 210023China

In this work,high-fidelity full-dimensional potential energy surfaces(PESs)of the ground(X^(2)A′)and first doublet excited(A^(2)A″)electronic states of HCO were constructed using neural network *** total,4624 high-level ab initio points have been used which were calculated at Davidson corrected internally contracted MRCI-F12 level of theory with a quite large basis set(ACV5Z)without any scaling *** with the results obtained from the scaled PESs of Ndenguéet al.,the absorption spectrum based on our PESs has slightly larger intensity,and the peak positions are shifted to smaller energy for dozens of *** is indicated that the scaling of potential energy may make some unpredictable difference on the dynamical ***,the resonance energies based on those scaled PESs are slightly closer to the current available experimental values than ***,the unscaled high-level PESs developed in this work might provide a platform for further experimental and theoretical photodissociation and collisional dynamic studies for HCO system.

关键词： Potential energy surface Photodissociation process Absorption spectrum Neural network Excited state

Interaction specific binding hotspots in Endonuclease colicin-immunity protein complex from MD simulations

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Science China Chemistry 2013年第8期56卷 1143-1151页

作者： YAO XueXia JI ChangGe xie daiqian ZHANG John Z.H. School of Chemistry and Chemical Engineering Nanjing University College of Engineering Nanjing Agricultural University State Key Laboratory of Precision Spectroscopy Department of PhysicsEast China Normal University Department of Chemistry New York University

The binding of Endonuclease colicin 9 (E9) by Immunity protein 9 (Im9) was found to involve some hotspots from helix III of Im9 on protein-protein interface that contribute the dominant binding energy to the *** the current work,MD simulations of the WT and three hotspot mutants (D51A,Y54A and Y55A of Im9) of the E9-Im9 complexes were carried out to investigate specific interaction mechanisms of these three hotspot *** changes of binding energy between the WT and mutants of the complex were computed by the MM/PBSA method using a polarized force field and were in excellent agreement with experiment values,verifying that these three residues were indeed hotspots of the binding *** decomposition analysis revealed that binding by D51 to E9 was dominated by electrostatic interaction due to the presence of the carboxyl group of Asp51 which hydrogen bonds to *** binding by hotspots Y54 and Y55,van der Waals interaction from the aromatic side chain of tyrosine provided the dominant *** comparison,calculation by using the standard (nonpolarizable) AMBER99SB force field produced binding energy changes from these mutations in opposite direction to the experimental *** hydrogen bond analysis showed that conformations sampled from MD simulation in the standard AMBER force field were distorted from the native state and they disrupted the inter-protein hydrogen bond network of the protein-protein *** current work further demonstrated that electrostatic polarization plays a critical role in modulating protein-protein binding.

关键词： protein-protein interaction binding hotspot mutation Endonuclease Colicin immunity protein MD simulation

State-to-state photodissociation dynamics of small molecules

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State-to-state photodissociation dynamics of small molecules