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First-Principles Study of Two Dimensional Transition Metal Phthalocyanine-Based Metal-Organic Frameworks in kagome Lattice

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Chinese Journal of Chemical Physics 2019年第5期32卷 563-571页

作者： Hao-qi Chen Huan Shan Ai-di Zhao Bin Li Hefei National Laboratory for Physical Sciences at the Microscale University of Science and Tech- nology of China Hefei 230026 China Synergetic Innovation Center of Quantum Information & Quantum Physics University of Science and Technology of China Hefei 230026 China

Transition metal phthalocyanines (TMPc) and relevant derivatives can act as pervasive molecules for their electronic, magnetic, and optical applications. Numerous researches based on TMPc are carried out, attempting to synthesize novel two-dimensional (2D) metal-organic frameworks. Recently, some 2D poly-TMPc frameworks including FePc [J. Am. Chem. Soc. 133, 1203 (2011)], CoPc [Chem. Commun. 51, 2836 (2015)], and Ni-NiPc [J. Mater. Chem. A 6, 1188 (2018)] frameworks have been successfully synthesized experimentally. Meanwhile, potential applications in catalysis, gas storage, and spintronics were predicted by theoretical studies. Here, we propose a new kind of 2D poly-TMPc frameworks with kagome lattice (denoted as kag-TMPc) and systematically investigate their electronic and magnetic properties by employing first-principles calculations. We have demonstrated that the 2D kag-MnPc framework displays quite stable ferromagnetic ordering with Curie temperature about 125 K as indicated by Monte Carlo simulations based on Heisenberg model and prefers out-of-plane easy-magnetization axis. The 2D kag-CrPc framework is an ideal candidate for S=2 kagome antiferromagnet with RT3 magnetic order. Particularly, the investigations on optical absorption suggest that when the TMPc molecules are self-assembled into 2D kag- TMPc frameworks, their absorption wave bands are broadened, especially in visible region.

关键词： Transition metal phthalocyanine Metal-organic framework kagome Curie temperature Magnetic order Optical absorption

Anisotropic Superconducting Properties of kagome Metal CsV_3Sb_5

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Chinese Physics Letters 2021年第5期38卷 121-125页

作者：倪顺利马晟张宇航袁洁杨海涛鲁邹有为王宁宁孙建平赵振李栋刘少博张华陈辉金魁程金光俞理周放董晓莉胡江平高鸿钧赵忠贤 Beijing National Laboratory for Condensed Matter Physics and Institute of Physics Chinese Academy of SciencesBeijing 100190China University of Chinese Academy of Sciences Beijing 100049China CAS Center for Excellence in Topological Quantum Computation University of Chinese Academy of SciencesBeijing 100190China Kavli Institute of Theoretical Sciences University of Chinese Academy of SciencesBeijing 100190China Songshan Lake Materials Laboratory Dongguan 523808China

We systematically measure the superconducting(SC)and mixed state properties of high-quality CsV_3 Sb_5 single crystals with T_c-3.5 K.We find that the upper critical field H_(c2)(T)exhibits a large anisotropic ratio of H_(c2)^(ab)/H_(c2)^c^9 at zero temperature and fitting its temperature dependence requires a minimum two-band effective model.Moreover,the ratio of the lower critical field,H_(c1)^(ab)/H_(c1)^c,is also found to be larger than 1,which indicates that the in-plane energy dispersion is strongly renormalized near Fermi energy.Both H_(c1)(T)and SC diamagnetic signal are found to change little initially below T_c-3.5 K and then to increase abruptly upon cooling to a characteristic temperature of-2.8 K.Furthermore,we identify a two-fold anisotropy of in-plane angular-dependent magnetoresistance in the mixed state.Interestingly,we find that,below the same characteristic T-2.8 K,the orientation of this two-fold anisotropy displays a peculiar twist by an angle of 60°characteristic of the kagome geometry.Our results suggest an intriguing superconducting state emerging in the complex environment of kagome lattice,which,at least,is partially driven by electron-electron correlation.

关键词： Anisotropic Superconducting Properties of kagome Metal CsV_3Sb_5 kagome

Emergence of magnetic order in kagome antiferromagnets

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Frontiers of physics 2019年第2期14卷 47-51页

作者： D. J. J. Farnell School of Dentistry Cardiff UniversityCardiff CF14 /XYWales UK

Exotic quantum spin liquid (QSL) states and fractionalized quasiparticles in frustrated magnets are of much current interest in theoretical and experimental studies of quantum magnetism. The kagome-lattice Heisenberg antiferromagnet (KAFM) provides a possible realization of just such novel topological states of matter. The kagome lattice shown in Fig. 1 is one of eleven Archimedean lattices in two spatial dimensions, where the word kagome itself means uweave pattera" in Japanese.

关键词： magnetic order kagome antiferromagnets quantum spin liquid (QSL)

kagome平面格栅结构的屈服面及裂尖塑性区分析

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力学学报 2008年第6期40卷 826-833页

作者：钱岳强邱信明张雄清华大学航天航空学院北京100084

分析了kagome格栅的等效刚度和屈服面.其屈服面奇异,由4段直线围成.利用该屈服面,估算了kagome具有Ⅰ型、Ⅱ型半无限大裂纹的裂尖塑性区,有限元计算验证了解析预测的准确性.与奇异屈服面相比,由Mises光滑屈服面给出的塑性区误差较大.因... 详细信息

分析了kagome格栅的等效刚度和屈服面.其屈服面奇异,由4段直线围成.利用该屈服面,估算了kagome具有Ⅰ型、Ⅱ型半无限大裂纹的裂尖塑性区,有限元计算验证了解析预测的准确性.与奇异屈服面相比,由Mises光滑屈服面给出的塑性区误差较大.因此只有弹性情况,可以将kagome等效为各向同性;若材料塑性,或应力场奇异性较强,kagome的强度依赖于主应力方向,不能用各向同性模型来描述.

关键词：塑性力学断裂 kagome 裂尖各向异性

kagome夹心板的多模态压电分流振动控制研究

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振动与冲击 2017年第19期36卷 60-65页

作者：郭空明徐亚兰西安电子科技大学机电工程学院应用力学研究中心西安710071

针对kagome夹心板的多模态振动控制问题,提出了一种独立模态压电分流振动控制方法。建立了结构与压电换能器耦合系统的有限元模型,之后详细阐述了kagome夹心板的独立模态压电分流振动控制策略,并针对自由振动问题提出了一种实用的多分... 详细信息

针对kagome夹心板的多模态振动控制问题,提出了一种独立模态压电分流振动控制方法。建立了结构与压电换能器耦合系统的有限元模型,之后详细阐述了kagome夹心板的独立模态压电分流振动控制策略,并针对自由振动问题提出了一种实用的多分流电路参数优化方法。结果表明,提出的控制方法能显著提高kagome夹心板结构的阻尼特性,加快自由振动的衰减,同时各压电分流电路之间具有很好的独立性。

关键词： kagome 夹心板多模态振动控制压电分流振动控制自由振动

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kagome蜂窝夹层平板的多功能优化设计

复合材料学报 2007年第3期24卷 109-115页

作者：王博王斌程耿东大连理工大学工程力学系工业装备结构分析国家重点实验室大连116023

采用“等效介质模型”,分析了复合材料夹层蜂窝平板的整体换热系数。在此基础上,针对轻质蜂窝(相对密度小于0.3),选取蜂窝面内等效剪切刚度表征夹层结构的承载能力,综合考虑散热能力和结构承载能力,比较了kagome蜂窝与传统的正三角形、... 详细信息

采用“等效介质模型”,分析了复合材料夹层蜂窝平板的整体换热系数。在此基础上,针对轻质蜂窝(相对密度小于0.3),选取蜂窝面内等效剪切刚度表征夹层结构的承载能力,综合考虑散热能力和结构承载能力,比较了kagome蜂窝与传统的正三角形、正方形和正六边形蜂窝的性能。结果显示kagome蜂窝不但散热性能很好,而且通过对蜂窝相对密度和尺寸的优化,在结构质量相同的情况下,kagome蜂窝的综合性能比传统蜂窝具有明显优势。

关键词： kagome 蜂窝材料多功能优化散热等效介质模型

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kagome点阵夹芯板的抗冲击性能研究

工程力学 2007年第8期24卷 86-92页

作者：郑华勇吴林志马力王新筑哈尔滨工业大学复合材料与结构研究所黑龙江哈尔滨150001

kagome点阵夹芯结构是近年来提出的一种力学性能十分优异的新型点阵夹芯结构。建立了3D-kagome点阵夹芯板在理想冲击载荷作用下的分析模型,将含有大量周期性单胞的芯子等效为实体板,得到了kagome芯子的等效本构关系,给出了芯子的等效强... 详细信息

kagome点阵夹芯结构是近年来提出的一种力学性能十分优异的新型点阵夹芯结构。建立了3D-kagome点阵夹芯板在理想冲击载荷作用下的分析模型,将含有大量周期性单胞的芯子等效为实体板,得到了kagome芯子的等效本构关系,给出了芯子的等效强度和刚度。采用有限元方法模拟3D-kagome夹芯板在理想冲击载荷作用下的响应,研究了板的最大挠度随芯子相对密度、芯子的厚度参数和冲击载荷大小的变化规律,得出了该结构抗冲击的最优化设计方案。与相同重量的实体板比较发现,3D-kagome点阵夹芯板在抵抗冲击、能量吸收和耗散等方面具有很大的优势。

关键词：工程力学轻结构点阵夹芯 kagome 冲击优化设计

Configurational Selectivity Study of Two-dimensional Covalent Organic Frameworks Isomers Containing D2h and C2 Building Blocks

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Chemical Research in Chinese Universities 2022年第2期38卷 639-642页

作者： ZHENG Xuhan ZHANG Lin XIE Chenxiao WANG Hui LIU Hui PAN Qingyan ZHAO Yingjie College of Polymer Science and Engineering Qingdao University of Science and TechnologyQingdao 266042P.R.China

The isomerization of covalent organic frameworks(COFs) materials is still a mysterious and attractive topic. Diversified monomer structures are still urgently needed to explore the in-depth mechanism of isomerization in these special COFs. This work provides a new D2h monomer for the construction of [D2h+C2] 2D COFs isomers. A new D2h monomer adopted here was proven to tend to form a single pore framework structure.

关键词： Covalent organic framework Isomerization kagome Dynamic covalent bond

悬臂kagome夹心板独立模态空间振动控制研究

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振动与冲击 2015年第2期34卷 55-60页

作者：郭空明江俊西安电子科技大学机电工程学院西安710071 西安交通大学机械结构强度与振动国家重点实验室西安710049

针对悬臂板挠度大、低频振动突出问题,对悬臂kagome夹心板的振动主动控制进行研究。建立结构及压电作动器有限元模型;将独立模态空间控制与模态观测器相结合,提出悬臂kagome夹心板的主动控制策略;针对突风载荷作用下夹心板基于独立模态... 详细信息

针对悬臂板挠度大、低频振动突出问题,对悬臂kagome夹心板的振动主动控制进行研究。建立结构及压电作动器有限元模型;将独立模态空间控制与模态观测器相结合,提出悬臂kagome夹心板的主动控制策略;针对突风载荷作用下夹心板基于独立模态空间的振动控制进行仿真,重点研究观测器极点对控制效果影响。结果表明,所提控制方法能显著提高悬臂kagome夹心板结构的阻尼特性,观测器衰减系数越大控制效果越好;该夹心板在振动控制方面较传统板结构优势明显。

关键词：悬臂板 kagome 夹心板独立模态空间控制模态观测器