...
  • 主题
高级搜索  >
历史搜索 清空历史
首页> 外文期刊>Physical review >First-principles modeling of localized d states with the GW@ LDA+U approach
【24h】

First-principles modeling of localized d states with the GW@ LDA+U approach

机译：用GW @ LDA + U方法对局部d状态进行第一性原理建模

获取原文
获取原文并翻译 | 示例
           
页面导航
  • 摘要
  • 著录项
  • 相似文献
  • 相关主题

摘要

First-principles modeling of systems with localized d states is currently a great challenge in condensed-matter physics. Density-functional theory in the standard local-density approximation (LDA) proves to be problematic. This can be partly overcome by including local Hubbard U corrections (LDA+U) but itinerant states are still treated on the LDA level. Many-body perturbation theory in the GW approach offers both a quasiparticle perspective (appropriate for itinerant states) and an exact treatment of exchange (appropriate for localized states), and is therefore promising for these systems. LDA+U has previously been viewed as an approximate GW scheme. We present here a derivation that is simpler and more general, starting from the static Coulomb-hole and screened exchange approximation to the GW self-energy. Following our previous work for f-electron systems [H. Jiang, R. I. Gomez-Abal, P. Rinke, and M. Scheffler, Phys. Rev. Lett. 102, 126403 (2009)] we conduct a systematic investigation of the GW method based on LDA+U(GW@LDA+U), as implemented in our recently developed all-electron GW code FHI-gap (Green's function with augmented plane waves) for a series of prototypical d-electron systems: (1) ScN with empty d states, (2) ZnS with semicore d states, and (3) late transition-metal oxides (MnO, FeO, CoO, and NiO) with partially occupied d states. We show that for ZnS and ScN, the GW band gaps only weakly depend on U but for the other transition-metal oxides the dependence on U is as strong as in LDA+U. These different trends can be understood in terms of changes in the hybridization and screening. Our work demonstrates that GW@LDA+U with "physical" values of U provides a balanced and accurate description of both localized and itinerant states.
机译：目前，具有局域d状态的系统的第一性原理建模在凝聚态物理中是一个巨大的挑战。标准局部密度近似（LDA）中的密度泛函理论被证明是有问题的。通过包括局部Hubbard U校正（LDA + U）可以部分克服此问题，但仍然在LDA级别上处理流动状态。 GW方法中的多体摄动理论既提供了准粒子观点（适用于流动状态），又提供了精确的交换处理（适用于局部状态），因此对于这些系统很有希望。 LDA + U以前被视为近似GW方案。从静态库仑孔和屏蔽交换近似到GW自能，我们在这里给出了一个更简单，更通用的推导。遵循我们先前对f电子系统所做的工作[H. Jiang，R。I. Gomez-Abal，P。Rinke和M. Scheffler，物理学。牧师102，126403（2009）]我们对基于LDA + U（GW @ LDA + U）的GW方法进行了系统的研究，该方法在我们最近开发的全电子GW代码FHI-gap（格林函数与增强平面波）中实现）对于一系列原型d电子系统：（1）具有空d态的ScN，（2）具有半芯d态的ZnS和（3）具有部分d的后期过渡金属氧化物（MnO，FeO，CoO和NiO）占领的d个州。我们表明，对于ZnS和ScN，GW带隙仅弱地依赖于U，但是对于其他过渡金属氧化物，其对U的依赖性与LDA + U一样强。这些不同的趋势可以通过杂交和筛选的变化来理解。我们的工作表明，具有U的“物理”值的GW @ LDA + U提供了对局部状态和迭代状态的平衡而准确的描述。

著录项

相似文献

  • 外文文献
  • 中文文献
  • 专利
获取原文

客服邮箱：kefu@zhangqiaokeyan.com

京公网安备：11010802029741号 ICP备案号：京ICP备15016152号-6 六维联合信息科技 (北京) 有限公司©版权所有

  • 客服微信

  • 服务号