TY  - THES
AU  - Schlipf, Martin
TI  - Heyd-Scuseria-Ernzerhof Screened-Exchange Hybrid Functional for Complex Materials: All-Electron Implementation and Application
VL  - 58
PB  - RWTH Aachen
VL  - Dr. (Univ.)
CY  - Jülich
M1  - PreJuSER-22714
SN  - 978-3-89336-857-0
T2  - Schriften des Forschungszentrums Jülich. Schlüsseltechnologien / Key Technologies
SP  - XV, 170 S.
PY  - 2012
N1  - Record converted from VDB: 12.11.2012
N1  - RWTH Aachen, Diss., 2012
AB  - The design of suitable materials for application in future devices requires a detailed understanding of their electronic and structural properties. The $\textit{ab initio}$ method density functional theory (DFT) has emerged as the most commonly applied materials. The limits of the predictive power of DFT are set by the availability of precise approximations to the exchange-correlation functional. In ths thesis, we developed a scheme to realize screened nonlocal potentials within the full-potential linearized augmented-plane-wave (FLAPW) method and applied it, in particular, to the screened Heyd-Scuseria-Ernzerhof (HSE) functional. Incorporating a certain fraction of nonlocal exchange, hybrid functionals improve on the conventional local functions by partly correcting for the spurios self interaction. This self interaction is most prominent in materials with localized states, so that we expect an improved description of transition-metal and rare-earth compounds. The strong localization of the $\textit{d}$ and $\textit{f}$ electrons in these materials complicates a description by pseudopotential methods, so that they are particularly suited for the all-electron FLAPW scheme. The nonlocal exchange is computationally very demanding, hence, we discuss two apprximations to improve the computationally very demanding, hence, we discuss two approximations to improve the computation time of hybrid functional calculations: a spacial restriction of the nonlocal exchange and the employment of a smaller$\textit{k}$-point mesh in the calculation of the nonlocal exchange. We demonstrate that both schemes are feasible for selected materials, but not in general for all materials. [...]
LB  - PUB:(DE-HGF)11 ; PUB:(DE-HGF)3
UR  - https://juser.fz-juelich.de/record/22714
ER  -