Dynamics and stability of divacancy defects in graphene

作     者：Youngkuk Kim Jisoon Ihm Euijoon Yoon Gun-Do Lee 

作者机构：Department of Physics and Astronomy Seoul National University Seoul 151-747 Republic of Korea Department of Materials Science and Engineering Seoul National University Seoul 151-742 Republic of Korea Department of Nano Science and Technology Graduate School of Convergence Science and Technology Seoul National University Suwon 433-270 Republic of Korea Department of Materials Science and Engineering WCU Hybrid Materials Program Seoul National University Seoul 151-742 Republic of Korea Energy Semiconductor Research Center Advanced Institutes of Convergence Technology Seoul National University Suwon 443-270 Korea 

出 版 物：《Physical Review B》 (Phys. Rev. B Condens. Matter Mater. Phys.)

年 卷 期：2011年第84卷第7期

页      面：075445-075445页

核心收录：

学科分类：0808[工学-电气工程] 0809[工学-电子科学与技术（可授工学、理学学位）] 07[理学] 0805[工学-材料科学与工程（可授工学、理学学位）] 0702[理学-物理学] 

基　　金：Ministry of Education, Science and Technology [2011-0000904, 2010-0012670, KRF-2006-341-C000015, R31-2008-000-10075-0] KIST through the Hybrid Computational Science Laboratory KISTI 

摘      要：A divacancy (DV) is one of the most abundant and most important defects in irradiated graphene, which modifies electronic and chemical properties of graphene. In this paper, we present ab initio calculations to study the dynamics and stability of DVs in graphene. Divacancies in graphene have various reconstructed structures, such as triple pentagon-triple heptagon (555-777) and pentagon-octagon-pentagon (5-8-5) patterns. A direct observation of the structural transformations between these reconstructions was recorded in transmission electron microscope images reported by Girit et al. in Science 323, 1705 (2009). We clarify the atomic structures of DVs observed in the experiment and investigate the atomic processes and energetics for the observed dynamical motions in great detail. It is found that a series of Stone–Wales-type transformations are responsible for the migration and structural transformations of DVs and that a pentagon-heptagon-heptagon-pentagon (5-7-7-5) defect appearing as an intermediate structure during the dynamical process plays an important role in the transformations of DVs.