期刊文献+
共找到5篇文章
< 1 >
每页显示 20 50 100
基于智能全局优化算法的理论结构预测 被引量:3
1
作者 高朋越 吕健 +1 位作者 王彦超 马琰铭 《物理》 北大核心 2017年第9期582-589,共8页
凝聚态物质内部的原子堆垛方式,即微观原子结构,是深入理解其各种宏观物理和化学性质的基础。近年来,随着基于群智理论的全局优化算法和第一性原理计算方法的发展,只根据物质的化学组分和外界条件,通过理论计算来确定或预测物质的微观... 凝聚态物质内部的原子堆垛方式,即微观原子结构,是深入理解其各种宏观物理和化学性质的基础。近年来,随着基于群智理论的全局优化算法和第一性原理计算方法的发展,只根据物质的化学组分和外界条件,通过理论计算来确定或预测物质的微观原子结构成为可能。文章将对目前国内外主要理论结构预测方法进行简要的概述,重点介绍基于群智算法的卡里普索(CALYPSO)结构预测方法的基本原理及其在凝聚态物质结构研究中的一些典型应用。 展开更多
关键词 全局优化算法 理论结构预测 粒子群优化 卡里普素方法
原文传递
N-(1-萘基)-琥珀酰亚胺化合物晶体结构的理论预测 被引量:4
2
作者 袁伟 李贺先 +1 位作者 王颖 王国昌 《物理化学学报》 SCIE CAS CSCD 北大核心 2006年第9期1071-1074,共4页
用MaterialsStudio软件对N-(1-萘基)-琥珀酰亚胺多晶粉末的X射线衍射数据进行衍射峰指标化、晶胞参数优化和空间群搜索等理论计算,可以确定晶体结构所属的晶系和空间群,并初步给出和多晶粉末衍射数据相近的晶胞参数;在已确定空间群范围... 用MaterialsStudio软件对N-(1-萘基)-琥珀酰亚胺多晶粉末的X射线衍射数据进行衍射峰指标化、晶胞参数优化和空间群搜索等理论计算,可以确定晶体结构所属的晶系和空间群,并初步给出和多晶粉末衍射数据相近的晶胞参数;在已确定空间群范围内,以密度泛函理论计算得到的最低能量构象作为初始分子结构,对N-(1-萘基)-琥珀酰亚胺多晶进行晶体结构理论预测,给出一系列假定的晶胞参数,从中可以找到和经上述计算给出的晶胞参数一致的晶体结构;对其进行晶胞参数优化后,得到晶体结构具有和多晶粉末X射线衍射数据相近的衍射曲线,并与已有的单晶数据相吻合. 展开更多
关键词 晶体结构理论预测 N-(1-萘基)-琥珀酰亚胺 多晶粉末X射线衍射数据 晶胞结构参数 空间群
下载PDF
Structural Investigation of Technetium-Diphosphonate Complex 99mTc-MDP
3
作者 邱玲 林建国 +2 位作者 居学海 贡雪东 罗世能 《Chinese Journal of Chemical Physics》 SCIE CAS CSCD 2011年第3期295-304,I0003,共11页
Density functional theory method has been employed to investigate the structures of the prototypical technetium-labeled diphosphonate complex 99mTc-MDP, where MDP represents methylenediphosphonic acid. A total of 14 t... Density functional theory method has been employed to investigate the structures of the prototypical technetium-labeled diphosphonate complex 99mTc-MDP, where MDP represents methylenediphosphonic acid. A total of 14 trial structures were generated by allowing for the geometric, conformational, charge, and spin isomerism. Based on the optimized structures and calculated energies at the B3LYP/LANL2DZ level, two stable isomers were determined for the title complex. And they were further studied systematically in comparison with the experimental structure. The basis sets 6-31G*(LANL2DZ for Tc), 6-31G*(cc-pVDZ-pp for Tc), and DGDZVP have also been employed in combination with the B3LYP functional to study the basis set effect on the geometries of isomers. The optimized structures agree well with the available experimental data, and the bond lengths are more sensitive to the basis set than the bond angles. The charge distributions were studied by the Mulliken population analysis and natural bond orbital analysis. The results reflect a significant ligand-to-metal electron donation. 展开更多
关键词 RADIOPHARMACEUTICAL 99mTc-methylenediphosphonate Structural prediction Density functional theory Basis set effect
下载PDF
Topological Properties of Complex Networks with Different Types of Nodes
4
作者 张娟 吴文丰 《Journal of Donghua University(English Edition)》 EI CAS 2009年第4期384-386,共3页
Nodes play different roles or have different functions in many natural and social networks.In this paper,a simple model with different types of nodes and deterministic selective linking rule is proposed.The structural... Nodes play different roles or have different functions in many natural and social networks.In this paper,a simple model with different types of nodes and deterministic selective linking rule is proposed.The structural properties by theoretical predictions are investigated that the given model exhibits a power-law distribution. 展开更多
关键词 power-law distribution degree distribution clustering coefficient mean-field method
下载PDF
Effect of triple-phase contact line on contact angle hysteresis 被引量:4
5
作者 YU Yang WU Qun +1 位作者 ZHANG Kai JI BaoHua 《Science China(Physics,Mechanics & Astronomy)》 SCIE EI CAS 2012年第6期1045-1050,共6页
Recent studies have shown that the triple-phase contact line has critical effect on the contact angle hysteresis of surfaces.In this study,patterned surfaces with various surface structures of different area fractions... Recent studies have shown that the triple-phase contact line has critical effect on the contact angle hysteresis of surfaces.In this study,patterned surfaces with various surface structures of different area fractions were prepared by electron etching on a silicon wafer.The advancing angle,receding angle and hysteresis angle of these surfaces were measured.Our experimental results showed that while the geometry of microstructure and contact line have a minor effect on the advancing angle,they have a significant effect on the receding angle and thus the hysteresis angle.We have shown that the effect of microstructure and the contact line can be described by a quantitative parameter termed the triple-phase line ratio.The theoretical predictions were in good agreement with our experimental results. 展开更多
关键词 contact angle hysteresis receding angle surface microstructure area fraction contact line ratio WETTING
原文传递
上一页 1 下一页 到第
使用帮助 返回顶部