Lateral band formation and hybridization in molecular monolayers: NTCDA on Ag(110) and Cu(100)
Lateral band formation and hybridization in molecular monolayers: NTCDA on Ag(110) and Cu(100)
复制标题
单分子层中的横向带形成和杂交：Ag(110) 和 Cu(100) 上的 NTCDA
DOI：
10.1103/physrevb.88.075437
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发表时间：
2013
影响因子：
3.7
通讯作者：
F. Reinert
中科院分区：
文献类型：
--
作者：
M. Wiessner;J. Kübert;V. Feyer;P. Puschnig;A. Schöll;F. Reinert
芳香族分子在金属表面的吸附导致分子和金属波函数的复杂重组。有机金属界面体系的各种过程，如电荷转移，分子和金属态之间的杂化，以及界面内分散带的形成已被证明。对于模型分子1，4，5，8-萘四甲酸二酐（NTCDA），我们比较了Ag（110）和Cu（100）上的高度有序的单分子膜，这使我们能够通过角分辨光电子能谱确定改变与衬底的耦合强度时界面电子结构的变化。与Ag（110）衬底的较强耦合沿着较短的光空穴寿命和NTCDA最低未占分子轨道与金属态的较强杂化。通过从头计算，我们发现，所观察到的带色散大大增强，由于与Ag（110）的相互作用，而横向密集的吸附几何形状的NTCDA在Cu（100）需要一个更大的分子间波函数重叠，和基板的存在下，没有进一步的带宽增强的结果。
The adsorption of aromatic molecules on metal surfaces leads to a complex reorganization of the molecular and metal wave functions. Various processes such as charge transfer, hybridization between molecular and metallic states, and the formation of dispersing bands within the interface have been demonstrated for organometallic interface systems. For the model molecule 1,4,5,8-naphthalenetetracarboxylic dianhydride (NTCDA), we compare highly ordered monolayers on Ag(110) and Cu(100), which allows us to identify changes of the interfacial electronic structure when altering the coupling strength with the substrate by means of angle-resolved photoelectron spectroscopy. The stronger coupling to the Ag(110) substrate goes along with a shorter photohole lifetime and a stronger hybridization of the NTCDA lowest unoccupied molecular orbital with metal states. Supported byab initiocalculations, we show that the observed band dispersion is greatly enhanced due to the interaction with Ag(110) while the laterally denser adsorption geometry of NTCDA on Cu(100) entails a larger intermolecular wave-function overlap, and the presence of the substrate results in no further bandwidth enhancement.