Self-healing of vacancy defects in single-layer graphene and silicene
Author
Özçelik, V. O.
Gurel, H. H.
Çıracı, Salim
Date
2013Source Title
Physical Review B - Condensed Matter and Materials Physics
Print ISSN
2469-9950
Electronic ISSN
2469-9969
Publisher
American Physical Society
Volume
88
Issue
4
Pages
045440-1 - 045440-11
Language
English
Type
ArticleItem Usage Stats
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Abstract
Self-healing mechanisms of vacancy defects in graphene and silicene are studied using first-principles calculations. We investigated host adatom adsorption, diffusion, vacancy formation, and revealed atomistic mechanisms in the healing of single, double, and triple vacancies of single-layer graphene and silicene. Silicon adatom, which is adsorbed to silicene at the top site forms a dumbbell-like structure by pushing one Si atom underneath. The asymmetric reconstruction of the single vacancy in graphene is induced by the magnetization through the rebonding of two dangling bonds and acquiring a significant magnetic moment through the remaining unsaturated dangling bond. In silicene, three twofold coordinated atoms surrounding the single vacancy become fourfold coordinated and nonmagnetic through rebonding. The energy gained through new bond formation becomes the driving force for the reconstruction. Under the external supply of host atoms, while the vacancy defects of graphene heal perfectly, the Stone-Wales defect can form in the course of healing of silicene vacancy. The electronic and magnetic properties of suspended, single-layer graphene and silicene are modified by reconstructed vacancy defects. © 2013 American Physical Society.