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第十三届全国量子化学会议

作者： Liu Yan Huang Yue-tian wenliang wang College of Chemistry and Environment Weinan Normal University School of Chemistry and Chemical Engineering Shaanxi Normal University

Trifluoromethyl sulfur pentafluoride（SFCF） has relatively high global warming potentials（GWP） than that of CO and almost any other molecule [ 1, 2 ]. Even more, SFCF has long atmospheric lifetime, ranging from several hundred to a few thousand years. Though the serious impact on the atmosphere since the powerful greenhouse effects, there is no knowledge of the measures to remove or decompose the gas effective ly. In this paper, the defluorination mechanisms of the reaction between SFCF and CH radical were investigated by using the density functional method. The energies were refined with the accurate model chemistr y method GMP. The results show that SFCF is easier to be attacked by the carbon atom of CH radical. In SFCF molecule, the F atom on the bond axis（Fa） is easier to be extracted by the carbon atom than others [the F atom perpendicular to the bond axis（Fb） or in-CF group（Fc）] because the barrier of TS1 is 26.9 and 92.7 kJ×mol lower than that of TS2 and TS3. The CVT/SCT rate constants for the first type of fluorine abstraction arecalculated in the temperature range of 200-2000 K. The tunneling effect is insignificant and becomes effective only at the lower temperature. Moreover, the variational effect is more significant forthe defluorination of SFCF at the site of F and F than F.

关键词： SF5CF3 CH3 defluorination mechanism theoretical calculation

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白皮杉醇PIC与OH自由基反应机理的理论研究

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高等学校化学学报 2015年第8期36卷 1588-1595页

作者：王帅王渭娜高志芳王文亮陕西省大分子科学重点实验室陕西师范大学化学化工学院西安710119

采用M05-2X/6-311++G(d,p)水平对白皮杉醇PIC清除OH自由基的气相反应机理进行了研究,并采用极化连续介质模型考察了极性溶剂对该反应机理的影响.结果表明,在气相和水溶液中OH自由基的抽氢反应均最易发生在B环的C4'OH位的酚羟基上,加成... 详细信息

采用M05-2X/6-311++G(d,p)水平对白皮杉醇PIC清除OH自由基的气相反应机理进行了研究,并采用极化连续介质模型考察了极性溶剂对该反应机理的影响.结果表明,在气相和水溶液中OH自由基的抽氢反应均最易发生在B环的C4'OH位的酚羟基上,加成反应优先在乙烯双键和C4'原子上进行.在298 K的气相条件下,抽氢与加成反应主通道总速率常数kCVT/SCTTotal分别为5.46×1015和2.72×1014L·mol-1·s-1,抽氢反应为优势通道,且抽氢与加成反应均具有负温度效应.

关键词：白皮杉醇 OH自由基反应机理密度泛函理论

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Theoretical studies on the electron transport property of chlorinated pentacenes derivatives

Theoretical studies on the electron transport property of ch...

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中国化学会第29届学术年会

作者： Yalu Guo wenliang wang Caibin Zhao Shiwei Yin Key Laboratory for Macromolecular Science of Shaanxi Province School of Chemistry and Chemical EngineeringShaanxi Normal University

To study the effect of chlorination on the charge-transport parameters of pentacene,a set of chlorinated pentacene derivatives（nCl-PENT-n）have been *** the geometries,electronic structures,reorganization energies,transfer integrals,and charge carrier transport parameters have been investigated with density functional theory（DFT）calculations and the inherent hopping *** the designed molecules,with the increase of the chlorine number,the frontier molecular orbital energies decrease,which could improve air *** on Marcus theory,the predicted hole mobilities（μh=0.46 cm2V-1s-1,μh,exp=0.2 cm2V-1s-1）and the electron mobilities（μe=0.61 cm2V-1s-1）values for6,13-dichloropentacene（DCP）crystal shows that DCP might be promising candidate as ambipolar OFET ***,μe of other chlorinated pentacene derivatives range from 2.47-9.01cm2V-1s-1 by means of the predicted crystal structures,which confirm that chlorination may be an effective method to design high performance n-type organic field-effect transistors.

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Theoretical study of thermal decomposition and isomerization Of 3-Me-1-heptyl radical

Theoretical study of thermal decomposition and isomerization...

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中国化学会第十二届全国量子化学会议

作者： Long Chen Weina wang Chunying Li Jian Lü wenliang wang School of Chemistry and Chemical Engineering Key Laboratory for Macromolecular Science of Shaanxi ProvinceShaanxi Normal University

A detailed theoretical study on the thermal decomposition and isomerization of 3-Me-1-heptyl radical at the CBS-QB3,B3LYP,B3PW91 and M06-2X levels of theory is *** result shows that the pyrolysis mechanism of 3-Me-1-heptyl radical mainly includes the isomerization and theβsite C-C bond scission,consisting of 25 *** is found that the structural parameters are generally insensitive to the used methods and basis *** standard reaction enthalpies for each elementary reaction involved in this system are also estimated at several density functional theory（DFT）methods together with cc-p VDZ basis set and the high level ab initio CBS-QB3 *** is concluded that the majority of isomerization reactions are exothermic and a few reactions are endothermic,whereas the decomposition reactions are generally *** distribution of 3-Me-1-heptyl radical pyrolysis is predicted based on the steady-state approximation,and the eventual products are ethylene（C2H4）,propylene（C3H6）,1-butylene（1-C4H8）,2-butylene（2-C4H8）*** goal of this work is to better understand the pyrolysis mechanism of 3-Me-1-heptyl radical and provide useful thermochemical and kinetic information.

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Thermal decomposition and isomerization of 1-heptyl radical: a computational investigation

Thermal decomposition and isomerization of 1-heptyl radical:...

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中国化学会第29届学术年会

作者： Long Chen Weina wang Chunying Li Jian Lü wenliang wang School of Chemistry and Chemical Engineering Key Laboratory for Macromolecular Science of Shaanxi Province Shaanxi Normal University

A detailed theoretical study on the thermal decomposition and isomerization of 1-heptyl radical at the CBS-QB3,BH＆HLYP,B3PW91,BLYP,MPW1PW91,and M06-2X levels of theory is *** result shows that the pyrolysis mechanism of 1-heptyl radical mainly includes the isomerization,the C-C and C-H bonds scission *** standard reaction enthalpies for each elementary reaction involved in this system are estimated at several density functional theory（DFT）methods together with cc-pVDZ basis set and the high level ab initio CBS-QB3 *** theoretical rate coefficients of conventional transition state theory with Eckart tunneling correction（TST/Eckart）for individual elementary reaction involved in the above reaction system are evaluated over the temperature range of 500-2500 *** calculated values are in good agreement with available experimental measurements and previous theoretical ***,the isomerization and decomposition reactions are selected to compare their relative importance at different *** is found that the isomerization process is more pronounced when the temperature below 1200 *** distribution of 1-heptyl radical pyrolysis is predicted based on the steady-state approximation,and the eventual products are ethylene（C2H4）,propylene（C3H6）,1-butylene（C4H8）,1-pentene（C5H10）,and 1-butylethylene（C6H12）.

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GaN-based light-emitting diodes on various substrates

GaN-based light-emitting diodes on various substrates

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中国晶体学会第六届学术年会暨会员代表大会（非线性光学及激光晶体材料分会）

作者： Guoqiang Li wenliang wang Yunhao Lin Haiyan wang Zhiting Lin State Key Laboratory of Luminescent Materials and Devices South China University of Technology Department of Electronic Materials South China University of Technology Department of Electronic Materials School of Materials Science and Engineering South China University of Technology

GaN and related Ⅲ-nitrides have attracted remarkable attentions aspromising materials for applications in optoelectronic devices, in particular, light-emitting diodes(LEDs). At present, sapphire is still the most popular commercial substrates for epitaxial growth of GaN-based LEDs. However, due to its relatively large lattice mismatch with GaN and low thermal conductivity, sapphire is not the most ideal substrate for GaN-based LEDs. Therefore, in order to obtain high-performance and high-power LEDs with relatively low cost, unconventional substrates different from sapphire, which are of low lattice mismatch with GaN, high thermal conductivity and low cost, have been tried as substitutes for sapphire. As a matter of fact, it is not easy to obtain high-quality Ⅲ-nitride films on those substrates due to various reasons. However, by developing a variety of techniques, distinctive progresses have been made during the last decade, with high-performance LEDs being successfully achieved on these unconventional substrates. This review focuses on the state-of-the-art of high-performance GaN-based LED materials and devices on unconventional substrates. The issues involved in the growth of GaN-based LED structures on each type of unconventional substrate are outlined, and the fundamental physics behind these issues are detailed. The corresponding solutions for Ⅲ-nitride growth, defect control, and chip processing for each type of unconventional substrate are discussed in depth, together with a brief introduction to some newly developed techniques in order to realize LED structures on unconventional substrates, which is very useful to understand the progress of physics in this field. The prospects of LEDs on unconventional substrates are also speculated in this report.

关键词： GaN Light-emitting diodes Substrates Crystalline defects Nonpolar

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Charge Transport Properties of tetrabenzoheptacene: The Effects of nitrogen and Phenyl Substitutions

Charge Transport Properties of tetrabenzoheptacene: The Effe...

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中国化学会第29届学术年会

作者： Lin Guan wenliang wang Caibin Zhao Fengyi Liu Key Laboratory for Macromolecular Science of Shaanxi Province School of Chemistry ＆ Chemical EngineeringShaanxi Normal University

The current work has investigated computationally the phenyl substituent and nitrogen doping effects on the electronic properties and charge transport parameters for tetrabenzoheptacene（TTBH）by means of density functional theory（DFT）calculations at the B3LYP/6-31G（d,p）*** show the nitrogen doping remarkably lowers the HOMO and LUMO levels,and favors the electron injection,while the phenyl substitution increases HOMO and *** addtion,calculated results also reveal that the nitrogen doping can largely decrease the hole reorganization energy,while the phenyl substitution tends to increasing *** with obtained electronic couplings,it is found that due to the steric effect of phenyl substitution,the largest Ve and Vh values are remarkable small in Ph-TTBH crystal,3.76 and 5.06 *** on predictedμvalues,TTH is found to prefer transporting holes（2.67cm2V-1s-1）,while TTBH favors electron transport（2.11cm2V-1s-1）.

关键词： Density functional theory Charge transport tetrabenzoheptacene

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Role of water clusters in the reaction of the simplest Criegee intermediate CH2OO with water vapour

Role of water clusters in the reaction of the simplest Crieg...

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第十三届全国量子化学会议

作者： Long Chen Yu Huang Junji Cao wenliang wang Key Lab of Aerosol Chemistry & Physics Institute of Earth EnvironmentChinese Academy of Sciences School of Chemistry and Chemical Engineering Key Laboratory for Macromolecular Science of Shaanxi ProvinceShaanxi Normal University

A comprehensive theoretical study on the role of water clusters(（HO）n, n=3-5) in the reaction of CHOO with water vapour is done at the CCSD（T）//M06-2 X/6-311+G（2 df,2 p） level of theory. Our simulation results show that the contribution of entropic effect is significantly increased with the increase in the number of water molecules involved. The main products of CHOO reaction with water vapour are α-hydroxymethyl hydroperoxide（HMHP） and its isomers. Contrary to the reaction of CHOO with unimolecular water(10.91 kcal·mol), the barriers of reactions with bi-and trimolecular water are further reduced to 5.25 and 4.75 kcal·mol, respectively. Among these three reactions, the predominant pathway is the reaction of CHOO with bimolecular water owing to its lower barrier and the high concentration of（HO）([（HO）] ≈ 2.47 × 10 molecules·cm). The presence of water clusters exhibits a dramatic catalytic effect in the CHOO reaction with bimolecular water as it lowers the energy barrier by 4.0 kcal·mol. The relative reaction rates, which are determined at temperatures from 273 to 323 K and 85% relative humidity（RH）, reveal that the most favorable pathway for the atmospheric removal of CHOO is indeed via its reaction with bimolecular water.

关键词： CH2OO Water clusters Reaction mechanisms Rate coefficient Relative reaction rates

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光学薄膜自动设计的多目标优化方法

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光学学报 2008年第10期28卷 2026-2030页

作者：王文梁熊胜明中国科学院光电技术研究所四川成都610209 中国科学院研究生院北京100039

光学薄膜中已使用的优化方法都是单目标寻优的,通过分析光学薄膜优化设计的原理,将薄膜设计的物理问题归结为混合离散变量的多目标优化设计的数学模型,并认为这是薄膜设计的一般性模型,现行的单目标优化算法只是这个模型的简化。基于这... 详细信息

光学薄膜中已使用的优化方法都是单目标寻优的,通过分析光学薄膜优化设计的原理,将薄膜设计的物理问题归结为混合离散变量的多目标优化设计的数学模型,并认为这是薄膜设计的一般性模型,现行的单目标优化算法只是这个模型的简化。基于这一新思路,并结合多目标优化算法的研究现状,采用了一种基于免疫应答原理的智能型多目标优化算法。该算法隐含并行处理能力,原理上是具备全局搜索能力的自适应随机性算法。将此算法运用到光学薄膜设计中,给出了一些优化的设计实例。结果表明,将多目标优化算法引入薄膜设计的新思路是可行的,将来会有较好的发展前景。

关键词：光学设计光学薄膜多目标优化免疫应答

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Petrogenesis of Adakitic Intrusive Rocksin Xu-Huai Area, Eastern China

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Global Geology 2003年第2期8卷 141-148页

作者： Qinghai wang, wenliang Xu, Dongyan wang, Jingqian LinCollege of Earth Sciences, Jilin University, Changchun, 130061 China College of Earth Sciences Jilin University Changchun 130061 China

The research of the petrology and the geochemistry of the Mosozoic intrusive rocks in Xu-Huai area indicated that they are mainly composition of dioritic porphyry and monzodioritic porphyry, and the features of the petrology and geochemistry of the Mosozoic intrusive rocks are extremely similar to those with the typical adakites. Combined with the petrography and the testimated results of the deep-seated xenoliths in the intrusive rocks, it indicates that the petrogenesis of the Mosozoic intrusive rocks could be resulted from the partial melting of amphibole-bearing garnet pyroxenite and garnet amphibolite in lower continental crust in this area.

关键词： adakite, petrogenesis, intrusive rocks, partial melting, Xu-Huai area

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