检索结果-南通市图书馆

Light(Science & Applications) 2023年第6期12卷 1029-1039页

作者： Fan Yang Qingsen Zeng Wei Dong Chunyuan Kang zexing qu Yue Zhao Haotong Wei Weitao Zheng Xiaoyu Zhang Bai Yang State Key Laboratory of Supramolecular Structure and Materials College of ChemistryJilin UniversityChangchun 130012China Department of Materials Science Key Laboratory of Mobile Materials MOEState Key Laboratory of Automotive Simulation and ControlJilin UniversityChangchun 130012China Institute of Theoretical Chemistry and Laboratory of Theoretical&Computational Chemistry Jilin UniversityChangchun 130023China

Film uniformity of solution-processed layers is the cornerstone of large-area perovskite light-emitting diodes,which is often determined by the‘coffee-ring effect’.Here we demonstrate a second factor that cannot be ignored is the solid-liquid interface interaction between substrate and precursor and can be optimized to eliminate rings.A perovskite film with rings can be formed when cations dominate the solid-liquid interface interaction;whereas smooth and homogeneous perovskite emitting layers are generated when anions and anion groups dominate the *** is due to the fact that the type of ions anchored to the substrate can determine how the subsequent film *** interfacial interaction is adjusted using carbonized polymer dots,who also orient the perovskite crystals and passivate their buried traps,enabling a 225 mm^(2) large-area perovskite light-emitting diode with a high efficiency of 20.2%.

关键词： interaction perovskite interaction

Split Operator Method in MM-VB Model: Application to Non-adiabatic Dynamics Simulations

维普期刊数据库评论

在线全文

维普期刊数据库

学校读者我要写书评

暂无评论

Split Operator Method in MM-VB Model: Application to Non-adi...

Construction of Diabatic and Adiabatic Potential Energy Surfaces of Li2 by Multistate Density Functional Theory

中国化学会第十二届全国量子化学会议

作者： zexing qu Chungen Liu Institute of Theoretical and Computational Chemistry School of Chemistry and Chemical Engineering Nanjing University

The mixed quantum/classical non-adiabatic dynamics simulations on the MM-VB model achieved great successful for the radiationless internal conversion processes of conjugated systems[1][2].In this non-adiabatic dynamics simulation,the total Hamiltonian is divided into a classical（nuclei）part and a quantum part（electron）.The nuclei move on a single adiabatic electronic potential energy surface（PES）following classical Newton equation,the PES is calculated on-the-fly by propagating the electronic wavefunction using time-dependent quantum *** convenient way of describing the non-adiabatic events around a conical intersection（CI）is through the"Trajectory Surface Hopping"（TSH）method,in which the switches between two adiabatic potential surfaces are controlled by the occupation probabilities in the non-adiabatic electronic wavefunction as time ***,in TSH approach,one critical issue is how to compute the time evolution of non-adiabatic electronic *** this work,the well-established split operator approximation method[3]is evaluated for its application in propagating the non-adiabatic *** will be highlighted for its high numerical precision comparable to the exact solution of the time-dependent Schr?dinger equation,while greatly cut down the time-cost,which could extend its capability to the system as large as 24π*** illustration,the radiationless 1Bu to 2Ag state conversion of mini-carotenoid has been systemically studied.

关键词：

来源： cnki会议评论

在线全文

cnki会议

学校读者我要写书评

暂无评论

Construction of Diabatic and Adiabatic Potential Energy Surf...

Development and application of quantum mechanics force field(QMRF)

第十五届全国化学动力学会议

作者：王萌 zexing qu Jiali Gao Institute of theoretical chemistry Jilin university Department of Chemistry Digital Technology Center and Supercomputing Institute University of Minnesota

In this study, we describe the total of 26 diabatic states for lithium dimer（Li2） to determine the adiabatic ground state and excited states and their potential energy surfaces using multistate density functional theory（MSDFT）. The diabatic states are defined by block localization of Kohn-Sham orbitals, which constrain the valence electronic states for each diabatic state in active orbital space. Their configuration interaction produces the adiabatic ground and excited states. In our diabatic calculations, we use PBEC functional which contains 100% HF exchange and PBE correlation functional. The off-diagonal Hamiltonian matrix element of coupling of two diabatic states is obtained from our constructed transition density. Our obtained potential energy surfaces are in good agreement with the high level theoretical results.

关键词： Diabatic potential energy surfaces Adiabatic potential energy surfaces Lithium dimer Multistate density functional theory

来源： cnki会议评论

在线全文

cnki会议

学校读者我要写书评

暂无评论

Development and application of quantum mechanics force field...

多组态密度泛函理论及透热与绝热势能面的构建

第十三届全国量子化学会议

作者： Jiali Gao Xin Chen zexing qu Institute of Theoretical Chemistry Jilin University Department of Chemistry Digital Technology Center and Supercomputing InstituteUniversity of Minnesota

Possessing the ability of converting heat into electricity and vice versa, thermoelectric materials can have a remarkable role in coping with the recent global energy issues.[1] Currently, organic thermoelectric materials(OTEs) have gained increasing attentions by virtue of being lightweight, flexible, environmentally friendly, solution processable and abundant.[2-3] However,OTEs need complex molecular design rules and vigilant doping. In contrast, metal organic frameworks(MOFs) can become highly efficient thermoelectric materials as they can have relatively higher electrical conductivities.[4] Here we apply density functional theory(DFT) to calculate the electronic band structures, the densities of states(DOS), as well as the thermoelectric properties by using Boltzmann transport theory for poly(MxNiethylenetetrathiolate)(MxNi-ett) based MOFs. The calculated power factors for Poly[Na(Niett)]and Poly[K(Ni-ett)] are found to agree well with the experimental results. We further predict that two new intrinsic semiconducting MOFs(Poly[NaNi(tetracene)] and Poly[NaNi(pentacene)]) will have the higher power factors than other MOFs semiconductors ever reported.

关键词： quantum mechanics force field combustion

来源： cnki会议评论

在线全文

cnki会议

学校读者我要写书评

暂无评论

高等学校化学学报 2015年第11期36卷 2236-2240页

作者：曲泽星高加力吉林大学理论化学研究所长春130023 明尼苏达大学化学学院超级计算研究所明尼苏达55455

介绍一种基于价键理论框架的多组态密度泛函理论(MSDFT),并以氢气(H2)分子解离过程及硝酸(HNO3)分子在水溶液中的质子转移过程为例,阐述了MSDFT方法的有效性.结果表明,对于H2分子的解离过程,MSDFT方法克服了以往单行列式密度泛函理论(D... 详细信息

介绍一种基于价键理论框架的多组态密度泛函理论(MSDFT),并以氢气(H2)分子解离过程及硝酸(HNO3)分子在水溶液中的质子转移过程为例,阐述了MSDFT方法的有效性.结果表明,对于H2分子的解离过程,MSDFT方法克服了以往单行列式密度泛函理论(DFT)的弊端,可给出正确的解离曲线,同时由于通过组态相互作用引入了静态电子相关的贡献,其计算精度可接近CASPT2水平;对于HNO3分子在水溶液中的质子转移过程,MSDFT方法可直接构建质子转移的透热势能曲线以及相应的非绝热耦合矩阵元,另一方面通过引入离子组态的贡献,可显著提升其计算精度,使其计算结果与精确结果相吻合.

关键词：多组态密度泛函理论透热电子态非绝热耦合势能面

在线全文

学校读者我要写书评

暂无评论

RDX分子内振动能量重分配的动力学研究

高等学校化学学报 2022年第10期43卷 283-289页

作者：张伶育张继龙曲泽星吉林大学化学学院理论化学研究所长春130023

基于从头算分子动力学(Born-oppenheimer moleculardynamics,BOMD)模拟,构建了环硝胺六氢-1,3,5-三硝基-1,3,5-三嗪(RDX)单分子不同振动模式之间的耦合矩阵,并计算了在不同加载能量下从低频振动模式到高频振动模式的最优能量传输路径.... 详细信息

基于从头算分子动力学(Born-oppenheimer moleculardynamics,BOMD)模拟,构建了环硝胺六氢-1,3,5-三硝基-1,3,5-三嗪(RDX)单分子不同振动模式之间的耦合矩阵,并计算了在不同加载能量下从低频振动模式到高频振动模式的最优能量传输路径.结果表明,RDX单分子中—NNO_(2)基团更有利于能量局域化,振动模式v_(3)和v_(4)在从低频振动模式到高频振动模式的能量传输过程中扮演着重要角色.通过对v_(3)和v_(4)两个振动模式的进一步分析发现,加载能量的不同会导致RDX单分子能量传输路径的不同.当加载能量较低时,RDX单分子倾向于从低频振动模式到中频振动模式再到高频振动模式的能量传输路径;当加载能量较高时,能量更倾向于从低频振动模式直接传输到高频振动模式上.揭示了RDX分子内振动耦合能量转移的微观机制,为进一步探索RDX将“机械能”转化为“化学能”的微观过程提供了理论基础.

关键词：环硝胺六氢-1,3,5-三硝基-1,3,5-三嗪分子内振动能量重分配能量转移从头算分子动力学

光诱导分步分态的苯型脱芳构化反应的理论研究

在线全文

学校读者我要写书评

暂无评论

高等学校化学学报 2021年第3期42卷 752-757页

作者：腾云洋曲泽星周中军黄旭日吉林大学理论化学研究所长春130021

采用密度泛函理论(DFT)和含时密度泛函理论(TD-DFT)研究了一类重要的含有杂原子的光催化苯型脱芳反应.研究结果表明,该脱芳反应是一个分步分态的[4+2]环加成反应,即前一步脱芳发生在三重态,后一步脱芳发生在单重态基态.其中,苯乙酮基团... 详细信息

采用密度泛函理论(DFT)和含时密度泛函理论(TD-DFT)研究了一类重要的含有杂原子的光催化苯型脱芳反应.研究结果表明,该脱芳反应是一个分步分态的[4+2]环加成反应,即前一步脱芳发生在三重态,后一步脱芳发生在单重态基态.其中,苯乙酮基团可被看作为光的接收装置,吸光后使得体系从单重态经内转换和系间窜越无能垒到达三重态,并在三重态完成质子转移生成具有反应活性的双烯,进而引发后续的脱芳反应.更重要的是,通过构建势能面发现该反应具有高度的立体选择性,与实验结果完全相符.

关键词：密度泛函理论激发态分子内质子转移脱芳构化立体选择性

在线全文

学校读者我要写书评

暂无评论

多共振热激活延迟荧光过程的理论研究

化学学报 2023年第2期81卷 124-130页

作者：张少秦李美清周中军曲泽星吉林大学化学学院理论化学研究所长春130023 吉林省计算中心长春130012

本工作借助第一性原理和动力学演化,系统地研究了四个叔丁基-咔唑及吩噻嗪取代的硼-氮化合物(BCz-BN、2PTZ-BN、Cz-PTZ-BN和2Cz-PTZ-BN)的多共振热激活延迟荧光的高效发光机制.结果表明上述分子T_(1)与T_(2)间的内转换速率远大于其它辐... 详细信息

本工作借助第一性原理和动力学演化,系统地研究了四个叔丁基-咔唑及吩噻嗪取代的硼-氮化合物(BCz-BN、2PTZ-BN、Cz-PTZ-BN和2Cz-PTZ-BN)的多共振热激活延迟荧光的高效发光机制.结果表明上述分子T_(1)与T_(2)间的内转换速率远大于其它辐射与非辐射速率,同时T_(2)到S_(1)的反向系间窜越速率也高于T_(1)到S_(1)的反向系间窜越速率,因此其多共振热激活延迟荧光过程应遵循T_(1)→T_(2)→S_(1)→S_(0)的路径.进一步动力学演化表明,T_(1)与T_(2)之间的内转换主要发生在演化初期,随着时间的推移,能量逐渐由T_(2)向S_(1)转移,并最终在S_(1)完成荧光发射.上述研究揭示了多共振延迟荧光的微观本质,为未来设计及合成新的多共振热激活延迟荧光分子提供了理论依据.

关键词：光致发光多共振热激活延迟荧光密度泛函理论激发态旋轨耦合反向系间窜越

同方期刊数据库

超声引导下穿刺活检鉴别病灶良恶性的价值探讨

在线全文

学校读者我要写书评

暂无评论

临床超声医学杂志 2018年第3期20卷 191-194页

作者：尹莉梁晓宁于泽兴卢瑞刚张颖巩丽焕曲鹏郭瑞君首都医科大学附属北京朝阳医院超声医学科北京市100020

目的探讨超声引导下穿刺活检(USGB)在病灶定性诊断中的价值。方法回顾性分析我院343例接受USGB肿物性质待查患者的临床及病理资料,计算其穿刺成功率、敏感性、特异性、误诊率、漏诊率、阳性预测值、阴性预测值、准确率、Youden指数、阳... 详细信息

目的探讨超声引导下穿刺活检(USGB)在病灶定性诊断中的价值。方法回顾性分析我院343例接受USGB肿物性质待查患者的临床及病理资料,计算其穿刺成功率、敏感性、特异性、误诊率、漏诊率、阳性预测值、阴性预测值、准确率、Youden指数、阳性似然比、阴性似然比及Kappa值。结果 343例患者共343个病灶,其中325个穿刺标本获得明确定性诊断,穿刺成功率94.75%。经术后病理证实,恶性202个,良性141个,USGB误诊10个,漏诊14个,准确率93.00%(319/343),敏感性、特异性、误诊率、漏诊率、阳性预测值、阴性预测值、Youden指数、阳性似然比及阴性似然比分别为93.07%(188/202)、92.91%(131/141)、7.09%(10/141)、6.93%(14/202)、94.95%(188/198)、90.34%(131/145)、85.98%,13.12及0.07。USGB与金标准比较总体一致性好(Kappa=0.86)。结论 USGB穿刺成功率高,诊断病灶良恶性准确率高,与金标准一致性好,对临床诊断及指导治疗有重要价值。

关键词：超声引导介入性病灶活检