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Structural stability and mechanical properties of TiB6:A CALYPSO-guided exploration for superhard applications 认领 引用
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作者 Bo Sun Yutong Zou +5 位作者 Tao Wang Yujia Wang Jinyu Liu Lili Gao Meiguang Zhang Miao Zhang 《Chinese Physics B》 SCIE EI CAS CSCD 2026年第5期48-56,共9页
Titanium-boron(Ti-B)compounds exhibit great promise as superhard materials due to titanium's low atomic mass and abundant valence electrons.In this work,we systematically investigated the crystal structures of TiB... Titanium-boron(Ti-B)compounds exhibit great promise as superhard materials due to titanium's low atomic mass and abundant valence electrons.In this work,we systematically investigated the crystal structures of TiB6under pressures ranging from 0-100 GPa using the CALYPSO algorithm combined with first-principles calculations.Phonon dispersion analysis and elastic-constant evaluations confirm the dynamic and mechanical stability of five predicted TiB6structures.Notably,theα-Amm2-TiB6structure was predicted to have a remarkable Vickers hardness of 56 GPa,as estimated by Chen's empirical model.All five structures are thermodynamically stable under ambient conditions,suggesting viable synthetic pathways.Their outstanding bulk moduli and ultrahigh hardness further classify them as potential incompressible and superhard materials.These theoretical insights lay a robust foundation for future experimental synthesis efforts. 展开更多
关键词 superhard materials transition metal borides Vickers hardness first-principles calculations CALYPSO method
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Edge加速器Calypso 4D电磁定位系统精确性评估 认领 引用 被引量：6
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作者 戴振晖 张白霖 +6 位作者 朱琳 朱远湖 杨耕 蔡春雅 李飞 张煜 王学涛 《中国医学物理学杂志》 CSCD 2018年第5期497-502,共6页
目的:研究Calypso 4D电磁定位系统的几何精度和电磁阵列对加速器射线的衰减。方法:分别把植入式转发器和表面转发器安装在体模上,对比Calypso测量的体模等中心位移和实际位移,分析系统的定位精度;使用指型电离室测量有和没有电磁阵列时... 目的:研究Calypso 4D电磁定位系统的几何精度和电磁阵列对加速器射线的衰减。方法:分别把植入式转发器和表面转发器安装在体模上,对比Calypso测量的体模等中心位移和实际位移,分析系统的定位精度;使用指型电离室测量有和没有电磁阵列时固体水内剂量,验证电磁阵列对射线的衰减;重复测量相同位置的体模等中心,评估系统稳定性。结果:植入式转发器的定位精度是(0.02±0.01)cm,表面转发器的定位精度是(0.01±0.01)cm;在机架角325°到35°范围内,6和10 MV能量电磁阵列对加速器射束的衰减低于2%,在305°和55°衰减低于3.4%;重复测量时出现偏移的标准差在0.012 cm以内。结论:Calypso系统定位精度能够稳定在亚毫米级,电磁阵列对射线的衰减在临床接受范围内,Calypso 4D电磁定位系统是精确、可靠的,能够大大提高放疗精度。 展开更多
关键词 Calypso 电磁定位 射线 体模
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The CALYPSO methodology for structure prediction 认领 引用 被引量：6
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作者 Qunchao Tong Jian Lv +1 位作者 Pengyue Gao Yanchao Wang 《Chinese Physics B》 SCIE EI CAS CSCD 2019年第10期22-29,共8页
Structure prediction methods have been widely used as a state-of-the-art tool for structure searches and materials discovery, leading to many theory-driven breakthroughs on discoveries of new materials. These methods ... Structure prediction methods have been widely used as a state-of-the-art tool for structure searches and materials discovery, leading to many theory-driven breakthroughs on discoveries of new materials. These methods generally involve the exploration of the potential energy surfaces of materials through various structure sampling techniques and optimization algorithms in conjunction with quantum mechanical calculations. By taking advantage of the general feature of materials potential energy surface and swarm-intelligence-based global optimization algorithms, we have developed the CALYPSO method for structure prediction, which has been widely used in fields as diverse as computational physics, chemistry, and materials science. In this review, we provide the basic theory of the CALYPSO method, placing particular emphasis on the principles of its various structure dealing methods. We also survey the current challenges faced by structure prediction methods and include an outlook on the future developments of CALYPSO in the conclusions. 展开更多
关键词 structure prediction CALYPSO method crystal structure potential energy surface
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Recent progress on the prediction of two-dimensional materials using CALYPSO 认领 引用 被引量：4
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作者 Cheng Tang Gurpreet Kour Aijun Du 《Chinese Physics B》 SCIE EI CAS CSCD 2019年第10期62-72,共11页
In recent years,structure design and predictions based on global optimization approach as implemented in CALYPSO software have gained great success in accelerating the discovery of novel two-dimensional(2D)materials.H... In recent years,structure design and predictions based on global optimization approach as implemented in CALYPSO software have gained great success in accelerating the discovery of novel two-dimensional(2D)materials.Here we highlight some most recent research progress on the prediction of novel 2D structures,involving elements,metal-free and metal-containing compounds using CALYPSO package.Particular emphasis will be given to those 2D materials that exhibit unique electronic and magnetic properties with great potentials for applications in novel electronics,optoelectronics,magnetronics,spintronics,and photovoltaics.Finally,we also comment on the challenges and perspectives for future discovery of multi-functional 2D materials. 展开更多
关键词 CALYPSO methodology two-dimensional materials structural prediction
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Cluster structure prediction via CALYPSO method 认领 引用 被引量：1
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作者 Yonghong Tian Weiguo Sun +2 位作者 Bole Chen Yuanyuan Jin Cheng Lu 《Chinese Physics B》 SCIE EI CAS CSCD 2019年第10期1-9,共9页
Cluster science as a bridge linking atomic molecular physics and condensed matter inspired the nanomaterials development in the past decades, ranging from the single-atom catalysis to ligand-protected noble metal clus... Cluster science as a bridge linking atomic molecular physics and condensed matter inspired the nanomaterials development in the past decades, ranging from the single-atom catalysis to ligand-protected noble metal clusters. The corresponding studies not only have been restricted to the search for the geometrical structures of clusters, but also have promoted the development of cluster-assembled materials as the building blocks. The CALYPSO cluster prediction method combined with other computational techniques have significantly stimulated the development of the cluster-based nanomaterials. In this review, we will summarize some good cases of cluster structure by CALYPSO method, which have also been successfully identified by the photoelectron spectra experiments. Beginning with the alkali-metal clusters, which serve as benchmarks, a series of studies are performed on the size-dependent elemental clusters which possess relatively high stability and interesting chemical physical properties. Special attentions are paid to the boron-based clusters because of their promising applications. The NbSi12 and BeB16 clusters, for example, are two classic representatives of the silicon-and boron-based clusters, which can be viewed as building blocks of nanotubes and borophene. This review offers a detailed description of the structural evolutions and electronic properties of medium-sized pure and doped clusters, which will advance fundamental knowledge of cluster-based nanomaterials and provide valuable information for further theoretical and experimental studies. 展开更多
关键词 CALYPSO method cluster structure prediction boron cluster silicon cluster
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Discovery of superhard materials via CALYPSO methodology 认领 引用
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作者 Shuangshuang Zhang Julong He +2 位作者 Zhisheng Zhao Dongli Yu Yongjun Tian 《Chinese Physics B》 SCIE EI CAS CSCD 2019年第10期10-21,共12页
The study of superhard materials plays a critical role in modern industrial applications due to their widespread applications as cutting tools, abrasives, exploitation drills, and coatings. The search for new superhar... The study of superhard materials plays a critical role in modern industrial applications due to their widespread applications as cutting tools, abrasives, exploitation drills, and coatings. The search for new superhard materials with superior performance remains a hot topic and is mainly considered as two classes of materials:(i) the light-element compounds in the B-C-N-O(-Si) system with strong and short covalent bonds, and(ii) the transition-element light-element compounds with strong covalent bonds frameworks and high valence electron density. In this paper, we review the recent achievements in the prediction of superhard materials mostly using the advanced CALYPSO methodology. A number of novel, superhard crystals of light-element compounds and transition-metal borides, carbides, and nitrides have been theoretically identified and some of them account well for the experimentally mysterious phases. To design superhard materials via CALYPSO methodology is independent of any known structural and experimental data, resulting in many remarkable structures accelerating the development of new superhard materials. 展开更多
关键词 CALYPSO superhard materials crystal structure prediction
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基于Calypso电磁实时跟踪系统的4D剂量验证 认领 引用
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作者 蔡春雅 戴振晖 +6 位作者 张白霖 朱琳 招什武 杨耕 朱远湖 李飞 王学涛 《中国医学物理学杂志》 CSCD 2019年第5期513-516,共4页
目的:研究基于Calypso电磁实时跟踪系统的4D剂量验证的可行性,评估Calypso引导对运动靶区放疗剂量精度提高的有效性。方法:将5 cm×5 cm、10 cm×10 cm方野、直径d=10 cm圆形野以及5例IMRT、5例VMAT放疗计划移植到Delta4三维剂... 目的:研究基于Calypso电磁实时跟踪系统的4D剂量验证的可行性,评估Calypso引导对运动靶区放疗剂量精度提高的有效性。方法:将5 cm×5 cm、10 cm×10 cm方野、直径d=10 cm圆形野以及5例IMRT、5例VMAT放疗计划移植到Delta4三维剂量验证系统,使用自主呼吸运动平台搭载Delta4模体进行SI方向上周期(T)=5 s,振幅(A)=±10 mm的往复运动,分别比较静态、动态无跟踪,以及使用Calypso实时跟踪系统运动阈值分别为±2、±3、±5 mm情况下Delta4实测的剂量分布和治疗计划系统剂量分布。结果:静态、动态测量Calypso运动阈值为±2、±3、±5 mm以及动态无跟踪时计划γ通过率的平均值分别为(97.5±2.4)%、(95.9±2.8)%、(93.9±3.8)%、(86.2±8.6)%、(65.0±11.1)%;与静态射野平均γ通过率比较,使用Calypso动态运动阈值为±2、±3 mm时γ通过率差异无统计学意义(P>0.05), Calypso动态运动阈值为±5 mm与动态无跟踪时γ通过率差异具有统计学差异(P<0.05)。结论:对于胸腹部肿瘤患者,基于Calypso实时电磁跟踪,结合Delta4三维验证系统对运动靶区进行实时4D剂量验证是可行的,使用Calypso跟踪运动肿瘤放疗时,剂量精度有明显提高。 展开更多
关键词 呼吸运动 4D剂量验证 实时跟踪 Calypso系统
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Calypso系统在肝脏立体定向放疗中的临床作用观察 认领 引用
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作者 詹梦娜 魏晓为 +2 位作者 何侠 尹丽 冯勇 《中国肿瘤外科杂志》 CAS 2022年第3期285-290,共6页
目的 探讨基于Calypso系统的电磁导航在门控肝立体定向放射治疗(SBRT)肿瘤实时追踪中的临床作用和价值。方法 选择2019年4月至2020年7月江苏省肿瘤医院,在Calypso电磁转发器的引导下,进行肝脏SBRT的4例患者为研究对象。所有患者在电磁... 目的 探讨基于Calypso系统的电磁导航在门控肝立体定向放射治疗(SBRT)肿瘤实时追踪中的临床作用和价值。方法 选择2019年4月至2020年7月江苏省肿瘤医院,在Calypso电磁转发器的引导下,进行肝脏SBRT的4例患者为研究对象。所有患者在电磁运动监测系统基础上配合呼气末屏气的呼吸门控治疗,分别记录每次治疗时间。评估放疗急性反应及远期不良反应,并在后续随访中评估疗效。采用调查问卷评估患者的治疗积极性及各个方面的主观结果。结果 所有患者转发器植入过程顺利,计划靶区是通过各个方向将临床靶区扩大5 mm边缘而形成。3例患者在治疗中观察到Ⅰ度骨髓抑制,无患者出现放射性肝损伤或其他不良反应。4例患者疗效评价均为疾病稳定。后续调查问卷显示所有患者在治疗过程中非常积极,自由呼吸患者反映舒适性更高。结论 基于Calypso电磁运动监测系统为追踪肝脏肿瘤靶区提供了一种实时直接有效的方法,值得临床推广应用。 展开更多
关键词 立体定向放射治疗 肝恶性肿瘤 追踪 Calypso
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基于Calypso方法分析(GaSb)_n(n=3-6)团簇的电子结构和性质 认领 引用
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作者 温世正 张淑萍 《广东化工》 CAS 2016年第18期25-26,共2页
本论文采用CALYPSO方法,基于全局搜索方法,结合密度泛函理论对(GaSb)n(n=3-6)团簇的结构进行预测和分析。我们对团簇的几何结构特征及键长变化等进行分析,并结合电子结构特征和电荷布居的分析,发现随着团簇的增加,Ga-Sb平均键长逐渐变短... 本论文采用CALYPSO方法,基于全局搜索方法,结合密度泛函理论对(GaSb)n(n=3-6)团簇的结构进行预测和分析。我们对团簇的几何结构特征及键长变化等进行分析,并结合电子结构特征和电荷布居的分析,发现随着团簇的增加,Ga-Sb平均键长逐渐变短,也说明了随着原子数增加,原子之间的作用更强,团簇更稳定。该研究有助于增强人们对GaSb团簇性质的理解和应用。 展开更多
关键词 GaSb团簇 CALYPSO方法 密度泛函理论 电荷转移
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The role of CALYPSO in the discovery of high-T_c hydrogen-rich superconductors 认领 引用 被引量：1
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作者 Wenwen Cui Yinwei Li 《Chinese Physics B》 SCIE EI CAS CSCD 2019年第10期56-61,共6页
Hydrogen-rich compounds are promising candidates for high-Tc or even room-temperature superconductors. The search for high-Tc hydrides poses a major experimental challenge because there are many known hydrides and eve... Hydrogen-rich compounds are promising candidates for high-Tc or even room-temperature superconductors. The search for high-Tc hydrides poses a major experimental challenge because there are many known hydrides and even more unknown hydrides with unusual stoichiometries under high pressure. The combination of crystal structure prediction and first-principles calculations has played an important role in the search for high-Tc hydrides, especially in guiding experimental synthesis. Crystal structure AnaLYsis by Particle Swarm Optimization(CALYPSO) is one of the most efficient methods for predicting stable or metastable structures from the chemical composition alone. This review summarizes the superconducting hydrides predicted using CALYPSO. We focus on two breakthroughs toward room-temperature superconductors initiated by CALYPSO: the prediction of high-Tc superconductivity in compressed hydrogen sulfide and lanthanum hydrides, both of which have been confirmed experimentally and have set new record Tc values. We also address the challenges and outlook in this field. 展开更多
关键词 CALYPSO structure prediction hydrogen-rich superconductors
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基于CALYPSO方法研究晶体和团簇结构 认领 引用
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作者 杨雪 张跃 崔张豪 《大学物理实验》 2019年第1期72-75,共4页
对CALYPSO预测方法的原理和核心技术进行了详细的介绍,并应用该方法分别研究了单质锂晶体和硼原子团簇结构的有关粒子空间分布构造问题,从而对CALYPSO方法有了更深入的了解和认识。
关键词 CALYPSO 结构预测 群智算法 粒子群
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Calypso具有多帐号管理能力的E-mail程序 认领 引用
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作者 小林 《软件世界》 1999年第9期127-127,共1页
关键词 电子邮件程序 帐号管理 Calypso
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基于CALYPSO方法的新型高能量密度材料设计 认领 引用 被引量：4
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作者 王晓丽 李建福 陈丽 《科学通报》 CAS CSCD 北大核心 2015年第27期2608-2615,共8页
高能量密度材料的研究由于其重大的研究意义和广泛的实际应用价值受到越来越广泛的关注.在众多含能材料家族中,聚合氮因其生成物为清洁无污染的氮,作为一种环境友好型的清洁能源材料,成为含能材料领域研究的热点.研究者从不同的角度出发... 高能量密度材料的研究由于其重大的研究意义和广泛的实际应用价值受到越来越广泛的关注.在众多含能材料家族中,聚合氮因其生成物为清洁无污染的氮,作为一种环境友好型的清洁能源材料,成为含能材料领域研究的热点.研究者从不同的角度出发,结合CALYPSO结构搜索技术通过第一性原理模拟对纯氮、碱金属叠氮化合物MN3(M=Li,Na,K,Rb,Cs)的高压行为进行了研究,期望得到结构稳定的聚合氮,并降低合成压强.本文在课题组前期研究的基础上,结合其他学者的研究内容,细致总结了以纯氮和碱金属叠氮化合物为前驱物,高压压致聚合氮过程中的相变及伴随相变发生的物理、化学性质的变化. 展开更多
关键词 CALYPSO 高压 高能量密度材料 叠氮化合物 第一性原理计算
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Structure search of two-dimensional systems using CALYPSO methodology 认领 引用 被引量：4
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作者 Pengyue Gao Bo Gao +4 位作者 Shaohua Lu Hanyu Liu Jian Lv Yanchao Wang Yanming Ma 《Frontiers of physics》 SCIE CSCD 2022年第2期121-134,共14页
The dimensionality of structures allows materials to be classified into zero-, one-, two-, and threedimensional systems. Two-dimensional (2D) systems have attracted a great deal of attention andtypically include surfa... The dimensionality of structures allows materials to be classified into zero-, one-, two-, and threedimensional systems. Two-dimensional (2D) systems have attracted a great deal of attention andtypically include surfaces, interfaces, and layered materials. Due to their varied properties, 2D systemshold promise for applications such as electronics, optoelectronics, magnetronics, and valleytronics.The design of 2D systems is an area of intensive research because of the rapid development of abinitio structure-searching methods. In this paper, we highlight recent research progress on acceleratingthe design of 2D systems using the CALYPSO methodology. Challenges and perspectives for futuredevelopments in 2D structure prediction methods are also presented. 展开更多
关键词 two-dimensional(2D)systems CALYPSO structure prediction
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结构搜索程序CALYPSO在新型超硬材料探索方面的应用 认领 引用 被引量：2
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作者 王渊旭 《科学通报》 CAS CSCD 北大核心 2015年第27期2601-2607,共7页
新型超硬材料的探索研究具有十分重要的应用价值.结构搜索程序不但能对一些实验合成但结构不确定的超硬材料的结构进行探索确认,而且能对实验尚未合成的超硬材料进行探索研究,对开发新型超硬材料十分有利.本文综述了利用结构搜索程序CAL... 新型超硬材料的探索研究具有十分重要的应用价值.结构搜索程序不但能对一些实验合成但结构不确定的超硬材料的结构进行探索确认,而且能对实验尚未合成的超硬材料进行探索研究,对开发新型超硬材料十分有利.本文综述了利用结构搜索程序CALYPSO对超硬材料(B,C,N超硬材料和过渡金属硼化物)进行的结构搜索研究,并展示了相应材料的硬度、弹性性质和电子结构性质等. 展开更多
关键词 超硬材料 结构搜索 CALYPSO 弹性 电子结构 硬度
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Structural stability and mechanical properties of NixMoyN ternary nitrides under high pressure:A first-principles study 认领 引用
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作者 Tao Wang Ming-Hong Wen +4 位作者 Kai-Xuan Wang Jia-Mei Liu Wei-Hua Wang Xu-Ying Wang Pei-Fang Li 《Chinese Physics B》 SCIE EI CAS CSCD 2026年第3期58-65,共8页
Transition metal nitrides have attracted significant attention due to their outstanding properties;however,studies on ternary systems under high pressure remain limited.In this work,we systematically investigated the ... Transition metal nitrides have attracted significant attention due to their outstanding properties;however,studies on ternary systems under high pressure remain limited.In this work,we systematically investigated the structures and properties of NiMoN compounds in the pressure range of 0-100 GPa by combining crystal structure analysis by particle swarm optimization(CALYPSO)structure prediction with first-principles calculations.To explore more structural possibilities,a large number of candidate structures were predicted and those with potential stability were selected.Among the newly predicted structures,a stable phase P213-NiMo4N and a low-energy metastable phase I4132-NiMo3N are proposed for the first time.The metastable structure I4132-NiMo3N lies 0.007 eV/atom above the convex hull,whereas the energy of the experimentally synthesized structure Fa3m-Ni3Mo3N is 0.036 eV/atom above the convex hull.Therefore,I4132-NiMo3N can likely be obtained through experimental synthesis.Phonon and elastic constant calculations confirm the stability of P213-NiMo4N and I4132-NiMo3N,while electronic structure calculations indicate that both exhibit metallic behavior,with Mo-4d orbitals making the primary contribution at the Fermi level.Mechanical property evaluations reveal that P213-NiMo4N exhibits high hardness,whereas I4132-NiMo3N shows relatively lower hardness but enhanced ductility.Under different pressures,both structures exhibit comparable ideal tensile strengths,but their failure mechanisms differ.This study broadens the known structural diversity of NiMoN ternary nitrides and provides theoretical insights into the exploration of high-pressure ternary nitrides. 展开更多
关键词 ternary nitride crystal structure CALYPSO high pressure
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CALYPSO结构预测方法 认领 引用 被引量：9
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作者 王彦超 吕健 马琰铭 《科学通报》 CAS CSCD 北大核心 2015年第27期2580-2587,共8页
凝聚态物质内部的原子排列方式,即结构,是深入理解其宏观物理和化学性质的重要信息.只根据物质的化学组分从理论上开展物质的结构预测是物理、化学和材料科学长期的期盼,但一直是个巨大挑战.基于结构对称性的分类检索思想,结合粒子群多... 凝聚态物质内部的原子排列方式,即结构,是深入理解其宏观物理和化学性质的重要信息.只根据物质的化学组分从理论上开展物质的结构预测是物理、化学和材料科学长期的期盼,但一直是个巨大挑战.基于结构对称性的分类检索思想,结合粒子群多目标优化算法,引入成键特征矩阵的结构表征方法,提出并发展了卡里普索(CALYPSO)结构预测方法,并在此基础上开发了拥有自主知识产权的同名结构预测软件包.该方法和软件只需给定材料的化学组分和外界条件(如压力),就可以预测材料的基态及亚稳态结构,并可以进行功能材料逆向设计.CALYPSO方法的高效可靠性已经在科研实践中得到了证实.目前该方法已经被广泛应用到三维晶体、二维层状材料和表面、零维的团簇等体系的结构研究领域,成为理论确定材料结构的有效手段. 展开更多
关键词 卡里普索 结构预测 群智算法
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First-principles insights into the high-pressure stability and electronic characteristics of molybdenum nitride 认领 引用 被引量：1
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作者 Tao Wang Ming-Hong Wen +4 位作者 Xin-Xin Zhang Wei-Hua Wang Jia-Mei Liu Xu-Ying Wang Pei-Fang Li 《Chinese Physics B》 SCIE EI CAS CSCD 2025年第3期142-150,共9页
Molybdenum nitride,renowned for its exceptional physical and chemical properties,has garnered extensive attention and research interest.In this study,we employed first-principles calculations and the CALYPSO structure... Molybdenum nitride,renowned for its exceptional physical and chemical properties,has garnered extensive attention and research interest.In this study,we employed first-principles calculations and the CALYPSO structure prediction method to conduct a comprehensive analysis of the crystal structures and electronic properties of molybdenum nitride(MoxN1-x)under high pressure.We discovered two novel high-pressure phases:Imm2-MoN3 and Cmmm-MoN4,and confirmed their stability through the analysis of elastic constants and phonon dispersion curves.Notably,the MoN4 phase,with its high Vickers hardness of 36.9 GPa,demonstrates potential as a hard material.The results of this study have broadened the range of known high-pressure phases of molybdenum nitride,providing the groundwork for future theoretical and experimental researches. 展开更多
关键词 molybdenum nitride CALYPSO crystal structure high pressure
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玻璃酸钠dn/dc值测定方法研究 认领 引用 被引量：1
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作者 张丽容 宋玉娟 +3 位作者 李京 范慧红 王悦 刘博 《中国药学杂志》 CAS CSCD 北大核心 2025年第4期407-411,共5页
目的 建立玻璃酸钠(sodium hyaluronate, SH)折光指数增量(dn/dc值)的通用测定方法,为实现SH相对分子质量与相对分子质量分布的准确测定奠定基础。方法 采用不同仪器、流动相和样品对SH的dn/dc值进行研究。结果 SH在0.1 mol·L^(-1... 目的 建立玻璃酸钠(sodium hyaluronate, SH)折光指数增量(dn/dc值)的通用测定方法,为实现SH相对分子质量与相对分子质量分布的准确测定奠定基础。方法 采用不同仪器、流动相和样品对SH的dn/dc值进行研究。结果 SH在0.1 mol·L-1硝酸钠溶液中更稳定,dn/dc值的相对标准偏差(RSD)均小于1.0%(n=3),建立了dn/dc值的准确测定方法。结论 新建测定方法简便、快速、准确,解决了SH的dn/dc值测定困难的问题,也为其他高分子物质相对分子质量与相对分子质量分布的精准测定提供了新的方法。 展开更多
关键词 玻璃酸钠 相对分子质量 分子排阻色谱-多角度激光光散射联用法 折光指数增量 CalypsoⅡ梯度混合仪
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Mg3Bn0/-(n=1~8)团簇几何结构、稳定性和特性研究 认领 引用
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作者 李成刚 赵海涛 +2 位作者 田浩 滕达 申梓刚 《北京化工大学学报（自然科学版）》 CAS CSCD 北大核心 2025年第3期55-64,共10页
基于卡利普索结构预测程序和密度泛函理论,系统地研究了Mg3Bn0/-(n=1~8)团簇的几何结构、稳定性和特性。首先,基于CCSD(T)/aug-cc-pvdz//B3LYP/6-311+G(d)下单点能的计算,Mg3B3-和Mg3B4-团簇全局极小结构具... 基于卡利普索结构预测程序和密度泛函理论,系统地研究了Mg3Bn0/-(n=1~8)团簇的几何结构、稳定性和特性。首先,基于CCSD(T)/aug-cc-pvdz//B3LYP/6-311+G(d)下单点能的计算,Mg3B3-和Mg3B4-团簇全局极小结构具有平面二维结构,其他团簇均呈现三维结构。当n=3、6、8时,中性和阴性团簇分别具有相同的对称性结构。其次,基于平均键能、二阶能量差分和HOMO-LUMO能隙分析,Mg3B6和Mg3B7-团簇在各自体系中具有相对高的稳定性。电荷和键级分析表明,电荷由镁原子向硼原子转移,B-B之间作用均为共价键,硼原子的加入削弱了镁原子之间的作用力。基于Multiwfn软件,拟合出了体系的光电子能谱、红外和拉曼光谱。最后,通过对Mg3B6和Mg3B7-团簇的热力学特性分析发现,随着温度升高,定容热容和标准熵随之增大,温度和两者之间分别存在近似二次函数关系。 展开更多
关键词 Mg3Bn0/-(n=1~8)团簇 卡利普索 几何结构 特性
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