新型D-π-A分子的设计及第一超极化率的理论研究

采用HF/6-31G(d)//CPHF/6-31G(d)方法研究了42个设计D-π-A分子的结构、分子的第一超极化率和其它物理性质.研究结果表明,取代基、分子内电荷转移、前线轨道能隙和偶极矩等对设计分子的第一超极化率有影响.本文的研究结果为设计和合成性能优良的有机非线性光学(NLO)材料提供理论指导.     

双氰亚甲基吡喃衍生物分子第一超极化率的理论研究

利用HF/631G(d)∥CPHF/631G(d)方法研究了双氰亚甲基吡喃衍生物的结构和分子的第一超极化率.根据计算结果讨论了取代基、分子内电荷转移、前线轨道能隙等对设计分子的第一超极化率的影响.计算结果表明设计的双氰亚甲基吡喃衍生物的β最大值高达51.87×10-30 m5/C,具有较高的非线性光学响应,同时分子的电子光谱最大吸收峰均在340～370 nm之间.具有较好的透光性,这都说明双氰亚甲基吡喃衍生物是一类具有潜在应用价值的二阶非线性光学材料.     

给体-受体共轭型希夫碱的分子第一超极化率的理论研究

采用HF／6-31G（d）／／TDHF／6-31G（d）方法研究了给体-受体共轭型希夫碱的几何结构和分子的第一超极化率,并与可利用的实验结果进行了比较．研究表明,这类希夫碱具有非平面的结构．另一方面,吸电子基和供电子基的种类,分子的共轭程度,基态与激发态之间的分子内电荷转移及HOMO-LUMO能隙对希夫碱分子的第一超极化率有明显的影响．     

1,2,3,4-四氢喹唑啉衍生物的第一超极化率的理论研究

用HF/6-31G（d）方法优化了1,2,3,4-四氢喹唑啉（THQ）衍生物的结构,并进行了频率分析以保证优化的结构是稳定的.利用CPHF/6-31G（d）方法计算了分子的第一超极化率β.通过计算考察和分析了外场频率、苯环上取代基的位置、分子内的电荷转移量、HOMO-LUMO的能隙对分子第一超极化率的影响.结果表明,THQ的6位取代衍生物有相对较大的第一超极化率.本文设计的大部分THQ衍生物分子具有较大的β0/λmax,它们是热稳定性好、透光性好的二阶NLO材料.     

氮蒽衍生物的分子第一超极化率的理论研究

用HF/6-31G(d)//CPHF/6-31G(d)方法获得了氮蒽衍生物分子的优化结构和分子第一超极化率.结果表明,在氮蒽的4位取代推电子基,11位取代吸电子基而得到的衍生物有相对较大的第一超极化率.苯环上取代基的种类、HOMO-LUMO的能隙及N1原子上的孤对电子对分子第一超极化率都有较大的影响.另一方面,设计的氮蒽衍生物具有较好的透光性和热稳定性,是一类具有潜在的应用价值的非线性光学材料.     

新设计的α-低聚呋喃-碱金属配合物的第一超极化率的理论研究

采用B3 LYP/6 - 31 G (d)//BHandHLYP/6 - 31 G ( d )方法研究了36个低聚呋喃-碱金属配合物的结构、分子的第一超极化率和其他物理性质.研究结果表明,体系的能隙、R2、极化率、碱金属间的距离、碱金属上的电荷转移以及氧环大小等对体系的第一超极化率有影响.本文的研究结果对设计和合成新型...     

具有大分子第一超极化率的有机发色团的从头算研究

用HF/6-31G方法对设计的14种D-π-A共轭分子进行了几何优化,然后用含时Harteer-Fork（TDHF）方法计算了这些分子的第一超极化率卢,并讨论了分子的第一超极化率与分子结构之问的关系．结果表明,具有高度离域的共轭体系及强的吸电子和供电子基团导致分子具有大的第一超极化率．     

典型轴手性D分子F被H取代的衍生物结构特性的理论研究

使用密度泛函理论的b3lyp方法,在b3lyp/6-31+g(d,p)理论水平上对D分子手性对映体D1的F被H取代的几种衍生物结构、红外振动频率、分子前线轨道进行了理论研究.结果表明:它们的解离产物及手型转变机制会不同;三种衍生物分子的HOMO和LUMO轨道,主要来源于骨架C原子p电子的贡献,F原子的p电子和手性C原子所在环上的H的s电子对前线分子轨道有很小的贡献.     

单、双、三硝基取代吡啶衍生物一阶超极化率的理论研究

采用AM1方法对单、双、三硝基取代衍生物几何结构进行优化,用从头算含时Hartree-Fock方程计算硝基吡啶衍生物分子的电子光谱,并在此基础上结合完全态求和公式自编程序计算了这些分子的一阶超极化率.从理论上讨论了不同取代位置对一阶超极化率性质的影响,发现1,6-二硝基吡啶和3,4,5-三硝基吡啶的一阶超极化率响应最大,并从微观上给予了解释.     

芦竹碱分子的密度泛函理论研究

用密度泛函理论,在B3LYP/6-311+G(d,p)水平上优化了芦竹碱分子的结构,给出了分子的键长、键角、二面角等参数,并对其进行了前线轨道分析和自然电荷分析,揭示了前线轨道、电荷分布与反应活性之间的关系.     

Markedness and its Interpretation in Language Use

Language markedness is a common phenomenon in languages, and is reflected from hearing, vision and sense, i.e. the variation in the three aspects such as phonology, morphology and semantics. This paper focuses on the interpretation of markedness in language use following the three perspectives, i.e. pragmatic interpretation, psychological interpretation and cognitive interpretation, with an aim to define the function of markedness.     

Features of Women's language

Language is a means of verbal communication. People use language to communicate with each other. In the society, no two speakers are exactly alike in the way of speaking. Some differences are due to age, gender, statue and personality. Above all, gender is one of the obvious reasons. The writer of this paper tries to describe the features of women＇s language from these perspectives： pronunciation, intonation, diction, subjects, grammar and discourse. From the discussion of the features of women＇s language, more attention should be paid to language use in social context. What＇s more, the linguistic phenomena in a speaking community can be understood more thoroughly.     

低渗透非均质砂岩油藏启动压力梯度研究

理论推导与室内实验相结合,建立了低渗透非均质砂岩油藏启动压力梯度确定方法。首先借助油藏流场与电场相似的原理,推导了非均质砂岩油藏启动压力梯度计算公式。其次基于稳定流实验方法,建立了非均质砂岩油藏启动压力梯度测试方法。结果表明:低渗透非均质砂岩油藏的启动压力梯度确定遵循两个等效原则。平面非均质油藏的启动压力梯度等于各级渗透率段的启动压力梯度关于长度的加权平均;纵向非均质油藏的启动压力梯度等于各渗透率层的启动压力梯度关于渗透率与渗流面积乘积的加权平均。研究成果可用于有效指导低渗透非均质砂岩油藏的合理井距确定,促进该类油藏的高效开发。     

On Tragic Consciousness In The Works By Ernest Hemingway

As an American modern novelist who were famous in the literary world, Hemingway was not a person who always followed the trend but a sharp observer. At the same time, he was a tragedy maestro, he paid great attention on existence, fate and end-result. The dramatis personae's tragedy of his works was an extreme limit by all means tragedy on the meaning of fearless challenge that failed. The beauty of tragedy was not produced on the destruction of life, but now this kind of value was in the impact activity. They performed for the reader about the tragedy on challenging for the limit and the death.     

Achieving Unusual States of Matter Under High Pressure

正The periodicity of the elements and the non-reactivity of the inner-shell electrons are two related principles of chemistry,rooted in the atomic shell structure.Within compounds,Group I elements,for example,invariably assume the+1 oxidation state,and their chemical properties differ completely from those of the p-block elements.These general rules govern our understanding of chemical structures and reactions.Using first principles calcula-     

Exchange-Correlation and Electronic Excitation Energies from Pairing Matrix Fluctuations

We have developed an adiabatic connection to formulate the ground-state exchange-correlation energy in terms of pairing matrix linear fluctuations.This formulation of the exchange-correlation energy opens a new channel for density functional approximations based on the many-body perturbation theory.We illustrate the potential of such approaches with an approximation based on the particle-particle Random Phase Approximation(pp-RPA).This re-     

Density Functional Theory for the Response of Periodic Systems to Electric Fields Based on the Vector Potential Approach

正The electronic and nuclear(structural/vibrational)response of 1D-3D nanoscale systems to electric fields gives rise to a host of optical,mechanical,spectral,etc.properties that are of high theoretical and applied interest.Due to the computational difficulty of treating such large systems it is convenient to model them as infinite and periodic(at least,in first approximation).The fundamental theoretical/computational problem in doing so is that     

On the Thermodynamic Limit for Responses to Static Electromagnetic Fields

For molecular systems,the quantum-mechanical treatment of their responses to static electromagnetic fields usually employs a scalar-potential treatment of the electric field and a vector-potential treatment of the magnetic field.Although the potential for each field separately is associated with the choice of an(unphysical)origin,the precise choice of the origin for the electrostatic field has little consequences for the results.This is different for the     

Call for Papers

<正>"The Journal of Shanghai Normal University:Mathematics"is published by Shanghai Normal University as regular issues of The Journal of Shanghai Normal University each year from 2014 in English.The editors-in-chief of the issues are professors Yuhao Cong and Maoan Han.The Journal of Shanghai Normal University was started in 1958 with     

Journal of Donghua University ( English Edition) Contents of Volume 31

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