Sagmeister Stephan, Ambrosch-Draxl Claudia
Atomistic Modelling and Design of Materials, University of Leoben, Franz-Josef-Strasse 18, A-8700, Leoben, Austria.
Phys Chem Chem Phys. 2009 Jun 14;11(22):4451-7. doi: 10.1039/b903676h. Epub 2009 Apr 21.
We perform first-principle calculations for the macroscopic dielectric function within an all-electron full-potential framework, i.e., the linearized augmented planewave (LAPW) method. To this extent we pursue two different routes, which are, on the one hand, many-body perturbation theory (MBPT) by solving the Bethe-Salpeter equation (BSE), and time-dependent density functional theory (TDDFT), on the other hand. The implementation into one program package, i.e., the EXC!TiNG code, allows a direct comparison of these approaches, in terms of accuracy as well as efficiency. We briefly review the theory, and describe in detail the quantities specific to the LAPW method. As an example we show the results for GaAs which is well-investigated in the literature, and hence serves as a stringent test case.
我们在全电子全势框架内，即线性缀加平面波（LAPW）方法中，对宏观介电函数进行第一性原理计算。在此过程中，我们采用了两种不同的方法，一方面是通过求解贝叶斯 - 萨尔皮特方程（BSE）的多体微扰理论（MBPT），另一方面是含时密度泛函理论（TDDFT）。将这两种方法集成到一个程序包，即EXC!TiNG代码中，能够在准确性和效率方面对这些方法进行直接比较。我们简要回顾了理论，并详细描述了LAPW方法所特有的量。作为一个例子，我们展示了砷化镓的计算结果，该材料在文献中已有充分研究，因此可作为一个严格的测试案例。
