Regensburg 2013 – scientific programme

Parts | Days | Selection | Search | Updates | Downloads | Help

TT: Fachverband Tiefe Temperaturen

TT 65: Focused Session: Frontiers of Electronic Structure Theory 7 (jointly with HL and O)

TT 65.12: Talk

Thursday, March 14, 2013, 18:45–19:00, H36

The linearized augmented lattice-adapted plane wave basis — •Gregor Michalicek and Stefan Blügel — Peter Grünberg Institut and Institute for Advanced Simulation, Forschungszentrum Jülich and JARA, 52425 Jülich, Germany

The full-potential linearized augmented plane wave method (FLAPW) is an all-electron electronic structure method that provides density functional results for complex solids with very high precision, irrespective of the chemical element of the solid. For this purpose the Kohn-Sham wavefunctions are expanded into LAPW basis functions. These are plane waves in an interstitial region (IR) that are augmented by atom-centered functions in non-overlapping spheres around each atom. The LAPW basis features many desirable properties that are a key component to the high precision of the FLAPW method.

In this talk we show that the capability of the FLAPW method can be kept with a modification of the basis-set that is numerically more efficient. We argue that the required plane-wave cut-off of the interstitial part of the LAPW basis results mostly from mathematical conditions and the efficiency of the LAPW description can be increased by incorporating more physics into the construction of this part of the basis. We propose a linearized augmented lattice-adapted plane wave basis ((LA)²PW) that replaces the plane waves in the IR by smart linear combinations of plane waves, show how to realize an efficient implementation of such a basis, and provide a construction principle for the linear combination of plane waves. The so constructed basis is evaluated in terms of precision and calculation runtime performance.