Graphene on Ir(111): Physisorption with Chemical Modulation
Graphene on Ir(111): Physisorption with Chemical Modulation
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DOI：
10.1103/physrevlett.107.036101
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发表时间：
2011-07-13
影响因子：
8.6
通讯作者：
Michely, Thomas
中科院分区：
文献类型：
--
作者：
Busse, Carsten;Lazic, Predrag;Michely, Thomas
应用非局域范德华密度泛函方法来计算石墨烯与 Ir(111) 的结合。计算出的 C 原子平均高度 (h) = 3.41 埃与通过 X 射线驻波技术测量的平均高度 (h) = (3.38 +/- 0.04) 埃的精确一致性为非局部泛函的适用性提供了基准。我们发现石墨烯与 Ir(111) 的键合是由于范德华相互作用与化学相互作用的反键合平均贡献所致。尽管其具有全局排斥特性，但在大型石墨烯莫尔晶胞的某些区域中观察到 Ir 基底和石墨烯 C 原子之间的电荷积累，这表明弱共价键的形成。
The nonlocal van der Waals density functional approach is applied to calculate the binding of graphene to Ir(111). The precise agreement of the calculated mean height (h) over bar = 3.41 angstrom of the C atoms with their mean height (h) over bar = (3.38 +/- 0.04) angstrom as measured by the x-ray standing wave technique provides a benchmark for the applicability of the nonlocal functional. We find bonding of graphene to Ir(111) to be due to the van der Waals interaction with an antibonding average contribution from chemical interaction. Despite its globally repulsive character, in certain areas of the large graphene moire unit cell charge accumulation between Ir substrate and graphene C atoms is observed, signaling a weak covalent bond formation.