Large-scale SCC-DFTB calculations of reconstructed polar ZnO surfaces
2014 (English)In: Surface Science, ISSN 0039-6028, E-ISSN 1879-2758, Vol. 628, 50-61 p.Article in journal (Refereed) Published
We present a theoretical study of a range of surface defects for the most abundant polar ZnO(0001)/(000 (1) over bar) surfaces using a tight binding approach with self-consistent charges (SCC-DFTB). We find that a combination of triangular pits at the Zn-terminated surface and a strongly ordered hexagonal defect pattern at the O-terminated surface constitutes a very stable reconstruction, in excellent agreement with experimental findings. On the whole, the SCC-DFTB method describes the polar surfaces of ZnO very well, and at a low computational cost which allows for the investigation of larger - and more realistic - surface structures compared to previous studies. Such large-scale calculations show that, at the Zn-terminated surface, the reconstruction results in a high density of one-layer deep triangular pit-like defects and surface vacancies which allow for a high configurational freedom and a vast variety of defect motifs. We also present extensive tests of the performance of the SCC-DFTB method in comparison with DFT results.
Place, publisher, year, edition, pages
2014. Vol. 628, 50-61 p.
ZnO, Polar surfaces, SCC-DFTB, DFT
Condensed Matter Physics Chemical Sciences
IdentifiersURN: urn:nbn:se:uu:diva-230913DOI: 10.1016/j.susc.2014.05.001ISI: 000340221200008OAI: oai:DiVA.org:uu-230913DiVA: diva2:743874