TY - JOUR
T1 - Screening in two dimensions
T2 - GW calculations for surfaces and thin films using the repeated-slab approach
AU - Freysoldt, Christoph
AU - Eggert, Philipp
AU - Rinke, Patrick
AU - Schindlmayr, Arno
AU - Scheffler, Matthias
PY - 2008/6/19
Y1 - 2008/6/19
N2 - In the context of photoelectron spectroscopy, the GW approach has developed into the method of choice for computing excitation spectra of weakly correlated bulk systems and their surfaces. To employ the established computational schemes that have been developed for three-dimensional crystals, two-dimensional systems are typically treated in the repeated-slab approach. In this work we critically examine this approach and identify three important aspects for which the treatment of long-range screening in two dimensions differs from the bulk: (1) anisotropy of the macroscopic screening, (2) k -point sampling parallel to the surface, (3) periodic repetition and slab-slab interaction. For prototypical semiconductor (silicon) and ionic (NaCl) thin films we quantify the individual contributions of points (1) to (3) and develop robust and efficient correction schemes derived from the classic theory of dielectric screening.
AB - In the context of photoelectron spectroscopy, the GW approach has developed into the method of choice for computing excitation spectra of weakly correlated bulk systems and their surfaces. To employ the established computational schemes that have been developed for three-dimensional crystals, two-dimensional systems are typically treated in the repeated-slab approach. In this work we critically examine this approach and identify three important aspects for which the treatment of long-range screening in two dimensions differs from the bulk: (1) anisotropy of the macroscopic screening, (2) k -point sampling parallel to the surface, (3) periodic repetition and slab-slab interaction. For prototypical semiconductor (silicon) and ionic (NaCl) thin films we quantify the individual contributions of points (1) to (3) and develop robust and efficient correction schemes derived from the classic theory of dielectric screening.
UR - http://www.scopus.com/inward/record.url?scp=45749128648&partnerID=8YFLogxK
U2 - 10.1103/PhysRevB.77.235428
DO - 10.1103/PhysRevB.77.235428
M3 - Article
AN - SCOPUS:45749128648
SN - 1098-0121
VL - 77
JO - Physical Review B - Condensed Matter and Materials Physics
JF - Physical Review B - Condensed Matter and Materials Physics
IS - 23
M1 - 235428
ER -