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arXiv 0903.3830cond-mat.mtrl-sci
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计算固体基本带隙的一种新的广义Kohn-Sham方法

A new generalized Kohn-Sham method for fundamental band-gaps in solids

Helen R. Eisenberg, Roi Baer

摘要:

我们开发了一种方法来计算固态基态性质和基本的带隙使用广义Kohn-Sham方法结合局域密度近似(LDA)功能与远程显式交换轨道功能。我们发现,当根据公式γ=A/(\eps_\ inf - \eps_\ tilde)选择射程参数时,对于各种不同类型的固体,基本带隙的预测值接近于实验值,其中\eps_\ inf是固体的光学介电常数,\eps_\ tilde= 0.84,A= 0.216a0^(-1)。对于大多数固体,范围参数γ很小(即,仅在长距离处需要显式交换),因此晶格常数和体积模量的预测值与基于常规LDA计算的预测值相似。

英文摘要:

We developed a method for calculating solid-state ground-state properties and fundamental band-gaps using a generalized Kohn-Sham approach combining a local density approximation (LDA) functional with a long-range explicit exchange orbital functional. We found that when the range parameter is selected according to the formula γ=A/(\eps_\inf - \eps_\tilde) where \eps_\inf is the optical dielectric constant of the solid and \eps_\tilde= 0.84 and A= 0.216a0^(-1), predictions of the fundamental band-gap close to the experimental values are obtained for a variety of solids of different types. For most solids the range parameter γis small (i.e. explicit exchange is needed only at long distances) so the predicted values for lattice constants and bulk modulii are similar to those based on conventional LDA calculations.

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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