arXivDaily arXiv每日学术速递 周一至周五更新
arXiv 1504.06259cond-mat.mtrl-sci
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杂化泛函对金属基本性质的错误预测

False Prediction of Fundamental Properties of Metals by Hybrid Functionals

Weiwei Gao, Tesfaye A. Abtew, Tianyi Cai, Y. Y. Sun, S. B. Zhang, Peihong Zhang

摘要:

一个不准确的帐户附近的费米能级EF的混合泛函预测几个重要的金属性质的电子状态的影响进行了研究。这些困难包括在EF处态密度(DOS)消失或严重抑制、显着加宽的价带宽、显着增强的电子-声子(el-ph)形变势以及过渡金属中磁矩的过高估计。错误地增强el-ph耦合计算的混合泛函可能会导致晶格不稳定性的错误预测。问题的主要根源在于对Fock交换能中的交换泛函的简单处理。短程库仑相互作用的使用消除了一些缺点,但基本问题保持不变。

英文摘要:

The repercussions of an inaccurate account of electronic states near the Fermi level EF by hybrid functionals in predicting several important metallic properties are investigated. The diffculties in- clude a vanishing or severely suppressed density of states (DOS) at EF, significantly widened valence bandwidth, greatly enhanced electron-phonon (el-ph) deformation potentials, and an overestimate of magnetic moment in transition metals. The erroneously enhanced el-ph coupling calculated by hybrid functionals may lead to a false prediction of lattice instability. The main culprit of the problem comes from the simplistic treatment of the exchange functional rooted in the original Fock exchange energy. The use of a short-ranged Coulomb interaction alleviates some of the drawbacks but the fundamental issues remain unchanged.

机构、总结、中文摘要均由AI分析而来,可能存在错误,请以论文正文为准。

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