检索结果-南通市图书馆

Electronic structure of ScN and YN： density-functional theory LDA and gw approximation calculations

Chinese Physics B 2007年第1期16卷 62-66页

作者：吕铁羽黄美纯 Department of Physics Xiamen University Xiamen 361005 China

The desirable physical properties of hardness, high temperature stability, and conductivity make the early transition metal nitrides important materials for various technological applications. To learn more about the nature of these materials, the local-density approximation（LDA） and gw approximation i.e. combination of the Green function G and the screened Coulomb interaction W, have been performed. This paper investigates the bulk electronic and physical properties of early transition metal mononitridcs, ScN and YN in the rocksalt structure. In this paper, the semicore electrons are regarded as valance electrons. ScN appears to be a semimetal, and YN is semiconductor with band gap of 0.142 eV within the LDA, but are in fact semiconductors with indirect band gaps of 1.244 and 0.544 eV respectively, as revealed by calculations performed using gw approximation.

关键词： ScN ,YN gw approximation LDA

来源：

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

Electronic band structure from first-principles Green’s function approach:theory and implementations

引用

中国化学前沿:英文版 2011年第4期6卷 253-268页

作者： Hong JIANG Beijing National Laboratory for Molecular Sciences State Key Laboratory of Rare Earth Material Chemistry and ApplicationInstitute of Theoretical and Computational ChemistryCollege of ChemistryPeking University100871BeijingChina

Electronic band structure is one of the most important intrinsic properties of a material,and is in particular crucial in electronic,photo-electronic and photo-catalytic ***-Sham Density-functional theory(KS-DFT)within currently available local or semi-local approximations to the exchange-correlation energy functional is problematic for the description of electronic band ***-body perturbation theory based on Green’s function(GF)provides a rigorous framework to describe excited-state properties of *** central ingredient of the GF-based many-body perturbation theory is the exchangecorrelation self-energy,which accounts for all nonclassical electron-electron interaction effects beyond the Hartree theory,and formally can be obtained by solving a set of complicated integro-differential equations,named Hedin’s *** gw approximation,in which the self-energy is simply a product of Green’s function and the screened Coulomb interaction(W),is currently the most accurate first-principles approach to describe electronic band structure properties of extended *** to KS-DFT,the computational efforts required for gw calculations are much *** numerical techniques or approximations have been developed to apply gw for realistic *** this paper,we give an overview of the theory of first-principles Green’s function approach in the gw approximation and review the state of the art for the implementation of gw in different representations and with different treatment of the frequency *** is hoped that further methodological developments will be inspired by this work so that the approach can be applied to more complicated and scientifically more interesting systems.

关键词： electronic band structure many-body perturbation theory gw approximation

来源：

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

Numerically Accurate gw Approach with LAPW+HLOs for First-principles Prediction of Band Gaps

Numerically Accurate GW Approach with LAPW+HLOs for First-pr...

引用

第十三届全国量子化学会议

作者：蒋鸿 College of Chemistry Peking University

Many-body perturbation theory in the gw approximation is currently the most accurate and robust first-principles approach to determine electronic band structure of weakly correlated insulating materials without any empirical input. Recent gw results for ZnO with a careful consideration of the convergence with respect to the number of unoccupied states have raised hot debates regarding the numerical accuracy of previously reported gw results using either pseudopotential planewaves or all-electron linearized augmented planewaves(LAPW).This work aims at presenting a numerically accurate gw approach based on LAPW extended by high-energy local orbitals(HLOs) [1]. It is shown that both the accuracy of unoccupied states and the completeness in the summation over states are crucial for numerically accurate gw calculations. By considering an extended set of semiconductors with relatively well established experimental band gaps, it was found that in general using HLOs-enhanced LAPW basis significantly improves the agreement between theoretically predicted band gaps by the semi-local density functional approximation based gw

关键词： gw approximation electronic band structure band gaps LAPW

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

欢迎您,

建议与咨询留下您的常用邮箱和电话号码，以便我们向您反馈解决方案和替代方法

时间限定

文献类型

馆藏选择

核心期刊

语言

文献类型

帮助

文字说明：

检索规则说明：

检索范例：

分类表

所选分类

限定检索结果

文献类型

馆藏范围

日期分布

学科分类号

主题

机构

作者

语言

在线全文

在线全文

在线全文

请选择保存的检索档案：

请选择收藏分类：

通借通还

欢迎您,

建议与咨询 留下您的常用邮箱和电话号码，以便我们向您反馈解决方案和替代方法

时间限定

文献类型

馆藏选择

核心期刊

语言

文献类型

帮助

文字说明：

检索规则说明：

检索范例：

分类表

所选分类

限定检索结果

文献类型

馆藏范围

日期分布

学科分类号

主题

机构

作者

语言

在线全文

在线全文

在线全文

请选择保存的检索档案： 新增检索档案 确定 取消

请选择收藏分类： 新增自定义分类 确定 取消

通借通还

建议与咨询留下您的常用邮箱和电话号码，以便我们向您反馈解决方案和替代方法

请选择保存的检索档案：

请选择收藏分类：