Eisenberg Helen R, Baer Roi
Institute of Chemistry and the Fritz Haber Center for Molecular Dynamics, The Hebrew University of Jerusalem, Jerusalem 91904, Israel.
Phys Chem Chem Phys. 2009 Jun 14;11(22):4674-80. doi: 10.1039/b902589h. Epub 2009 May 5.
We developed a method for calculating the ground-state properties and fundamental band-gaps of solids, 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 gamma=A/(epsiloninfinity-epsilon) where epsiloninfinity is the optical dielectric constant of the solid and epsilon=0.84 and A=0.216 a0(-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 gamma is small (i.e. explicit exchange is needed only at long distances) so the predicted values for lattice constants and bulk moduli are similar to those based on conventional LDA calculations. Preliminary calculations on silicon give a general band structure in good agreement with experiment.
我们开发了一种计算固体基态性质和基本带隙的方法，该方法采用广义Kohn-Sham方法，将局域密度近似（LDA）泛函与长程显式交换轨道泛函相结合。我们发现，当根据公式gamma=A/(epsiloninfinity-epsilon)选择范围参数时，其中epsiloninfinity是固体的光学介电常数，epsilon = 0.84且A = 0.216 a0(-1)，对于各种不同类型的固体，可以得到接近实验值的基本带隙预测。对于大多数固体，范围参数gamma很小（即仅在长距离处需要显式交换），因此晶格常数和体模量的预测值与基于传统LDA计算的值相似。对硅的初步计算给出了与实验结果吻合良好的一般能带结构。
