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Mapping frontier molecular orbitals using photocurrents

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Science China Materials 2023年第9期66卷 3761-3762页

作者： Ping Zhou J.Fraser Stoddart Hongliang Chen Stoddart Institute of Molecular Science Department of ChemistryZhejiang UniversityHangzhou 310027China ZJU-Hangzhou Global Scientific and Technological Innovation Center Zhejiang UniversityHangzhou 311215China Department of Chemistry Northwestern University2145 Sheridan RoadEvanstonIllinois 60208USA School of Chemistry University of New South WalesSydneyNSW 2052Australia

In the regime of coherent transport, the conductance of a molecular junction is governed(Fig. 1a) by the probability of electron transmission between the metal electrodes, a physica property which is affected significantly by the hybridization of frontier molecular orbitals(FMOs) with the continuous band of energy levels on the electrodes.

关键词： frontier molecular orbitals

Molecular calculations for HeH^+ with two-center correlated orbitals

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Science China Chemistry 2009年第12期52卷 2249-2256页

作者： DOU YuSheng TANG Hong BAI MingZe Institute of Computational Chemistry Chongqing University of Posts and TelecommunicationsChongqing 400065China Department of Physical Sciences Nicholls State UniversityThibodaux 70310USA

A two-center correlated orbital approach was used to calculate the electronic ground state energy for the HeH+ molecular ion. The wavefunctions were constructed from the exact solution of the Schrdinger equation for the HeH++ problem in prolate-spheroidal coordinates taken together with a Hylleraas type correlation factor. With a simple single term wavefunction,we obtained ground state energy of -2.95308691 hartree without any variational parameters in the calculation. When a two-configuration-state wavefunction was used and effective charges were allowed to be adjusted,we found an energy of -2.97384868 hartree,which is to be compared with -2.97869074 hartree obtained by an 83 term configuration interaction wavefunction or -2.97364338 hartree by an ab initio calculation (at the MP4(SDQ)/6-311++G(3df,3dp) level) using the well-known "canned" code.

关键词： HeH+ two-center orbitals prolate-spheroidal coordinates correlation function

Quantum Monte Carlo method of localized molecular orbitals

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Chinese Science Bulletin 1995年第11期40卷 912-915页

作者：黄宏新曾跃王祥盛 Department of Chemistry Hunan Normal University Changsha 410081 China

The fixed-node quantum Monte Carlo (FNQMC) method is one of the most accuratemethods, with which Schrdinger equation could be solved including 80%--100% of thecorrelation energies for the molecules with 2-10 electrons. However, the method hassome imperfections, i.e. (i) parametric numbers are too many to be optimized, (ii) the cuspcondition of the trial function cannot be satisfied.

关键词： fixed-node quantum Monte Carlo method localized molecular orbitals cusp conditions.

INTERACTION OF WALSH- AND π-orbitals——PHOTOELECTRON SPECTRA OF CYCLOPROPYL SUBSTITUTED BENZENES

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Science China Chemistry 1982年第3期 236-249页

作者：王建祺,EVIHONEGGER,EDGARHEILBRONNER,ANDREASSCHMELZER The Sixth Department of Beijing Institute of Technology Physikalisch-Chemisches Institut Universitat Basel Basel Switzerland Physikalisch-Chemisches Institut Universitat Basel Basel Switzerland Physikalisch-Chemisches Institut Universitat Basel Basel Switzerland

In this paper the photoelectron spectra of a series of cyclopropyl substituted benzenes arerecorded and discussed. Although their interpretation is made difficult by conformational pro-blems, with the possible exception of hexacyclopropyl benzene (12), it is confirmed that theWalsh orbitals of the cyclopropyl group interact appreciably with the π-system to which theyare attached in both the bisected and perpendicular conformation. The ratio of the cross-terms is B(eA, 2p)/B(es,2p)≈1.4 rather than a much larger number suggested by thetraditional diagrams for the Walsh orbitals. It is shown that a representation, in terms ofof localized bond orbitals derived from an STO-3G model, is more appropriate and heuristi-cally useful.

关键词：兀一 AND INTERACTION OF WALSH orbitals PHOTOELECTRON SPECTRA OF CYCLOPROPYL SUBSTITUTED BENZENES STO

Generalized orbitals under the Influence of 2D Central and Noncentral Forces

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World Journal of Mechanics 2014年第10期4卷 303-308页

作者： Haiduke Sarafian The Pennsylvania State University University College York USA

In polar coordinate system, we consider fifteen classes of forces resulting in unlimited undiscovered orbitals. The classic conic orbits are one of the special subclasses of the fifteen classes. Among the rest of the forces, we show a few instances displaying typical fresh orbitals. Aside from the common theoretical foundation, the specifics of the orbitals are given by the solution of corresponding equations of motion. These are coupled nonlinear differential equations. Solving these equations numerically, utilizing a Computer Algebra System such as Mathematica is conducive to the orbits. Simulation of the orbitals provides a visual understanding about the motion under the influence of the generalized noncentral forces.

关键词： Generalized orbitals Noncentral Forces Mathematica

A Band Theory Perspective on Molecular orbitals in Complex Oxides

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Journal of Modern Physics 2019年第8期10卷 953-965页

作者： Kateryna Foyevtsova George A. Sawatzky Department of Physics & Astronomy University of British Columbia Vancouver BC Canada Stewart Blusson Quantum Matter Institute University of British Columbia Vancouver BC Canada

In view of the growing interest in molecular orbitals (MOs) encountered in certain complex oxides, we review some of their properties from the band theory perspective and provide detailed examples based on real materials. Our discussion includes some technical aspects of identifying MOs in electronic structure calculations and considers cases when MOs can be both orthogonal and non-orthogonal. We also describe orthonormalization of MOs, a procedure converting them into Wannier functions, and discuss the problem of Wannier functions possibly being rather spatially extended and how using MO, rather than atomic orbital, based effective Hamiltonians might be a better choice in describing certain strongly correlated systems as well as systems with strong electron-phonon coupling. Furthermore, we address the problem of strongly correlated MOs and how it can be treated in band theory calculations.

关键词： Electronic Structure of Solids Molecular orbitals Complex Oxides Negative Charge-Transfer Insulators

A new algorithm for inactive orbital optimization in valence bond theory

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Science China Chemistry 2009年第11期52卷 1879-1884页

作者： CHEN ZhenHua ZHANG QianEr WU Wei State Key Laboratory of Physical Chemistry of Solid Surfaces and Department of ChemistryCollege of Chemistry and Chemical EngineeringXiamen UniversityXiamen 361005China

This paper presents an efficient algorithm for energy gradients in valence bond self-consistent field(VBSCF) method with non-orthogonal *** frozen core approximation method is extended to the case of non-orthogonal *** expressions for the total energy and its gradients are presented by introducing auxiliary orbitals,where inactive orbitals are orthogonal,while active orbitals are non-orthogonal themselves but orthogonal to inactive *** is shown that our new algorithm has a low scaling of(Na+1)m4,where Na and m are the numbers of the active orbitals and basis functions,respectively,and is more efficient than the existing VBSCF algorithms.

关键词： valence bond theory non-orthogonal orbitals gradient

Analysis of the Electronic Structure of 1-(4-Aminobutyl)-3-methylimidazolium Chloride via DFT Method

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Chinese Journal of Structural Chemistry 2019年第1期38卷 53-60,2页

作者： JIA Xin-Gang HU Xiao-Ling SU Ke-He WANG Wen-Zhen GU Xue-Fan School of Natural and Applied Sciences Northwestern Polytechnical University Chemistry and Chemical Engineering College Xi`an Shiyou University

Density functional theory and natural bond orbital analysis are applied to study the microelectronic structural properties of 1-(4-aminobutyl)-3-methylimidazolium chloride(C_4NH_2C_1imCl). We obtain 48 stable cation conformers at the B3LYP/6-311++G(d, p) level of theory. When the Cl anion is located at different positions around the two stable cation conformers,optimization and frequency are calculated at the same level of theory, and seven stable C_4NH_2C_1imCl structures are obtained. Ion-pair association energies, natural population analysis(NPA) charges, and the second-order stabilization energies are also calculated. Results show that three energy-degenerated states are present in seven conformers. The calculated ion-pair association energy, NPA charges, and second-order stabilization energy values are the same as those with the same energy level conformers. Finally, H bond formation in the molecule is analyzed by the interactions of frontier molecular orbitals. The lone pair of N(11) atom in the amino group exhibits higher reactivity than that of the N(4) atom in the ring.

关键词： ionic liquids density functional theory conformation frontier orbitals

BH_3及其等电子分子片的杂化轨道和轨道相互作用

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化学研究与应用 1989年第1期1卷 75-78页

作者：曹阳王友良郭进苏州大学化学系广西师范大学化学系苏州87级研究生

本文在文[1—3]和MNDO分子轨道计算的基础上,分析一些等电子分子片X(BH?、BF3、CH3+、CF3+)的前线杂化轨道,讨论它们同配体L（H-、CO、CN-、NC-、NH3）的轨道相互作用,从而研究X+L→XL反应的进程和产物XL分子稳定结构。

关键词： BH3 Hybrid orbitals orbital interactions.