Adsorption structure and scanning tunneling data of a prototype organic-inorganic interface: PTCDA on Ag(111)
Adsorption structure and scanning tunneling data of a prototype organic-inorganic interface: PTCDA on Ag(111)
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DOI：
10.1103/physrevb.76.115421
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发表时间：
2007-09-01
影响因子：
3.7
通讯作者：
Tautz, Frank Stefan
中科院分区：
文献类型：
--
作者：
Rohlfing, Michael;Temirov, Ruslan;Tautz, Frank Stefan
本文采用密度泛函理论计算了3，4，9，10-二萘嵌苯四甲酸二酐在Ag（111）表面的单层吸附，详细研究了该吸附体系的结构和电子性质。使用局域密度近似作为交换相关泛函的最佳选择，我们讨论了分子内部的键长，由于吸附的分子的变形，以及它们相对于衬底和彼此的位置和取向。基于计算的几何和电子结构，我们计算扫描隧道显微镜和光谱数据内的Tersoff-Hamann框架[B。31，805（1985）]。为此，二维傅里叶变换方法和空间外推技术来评估样品波函数的尖端位置。我们获得恒流图像和光谱数据，揭示了系统的电子结构的详细信息。此外，我们还用低温扫描隧道显微镜和扫描隧道光谱测量了相同的数据。我们的测量数据和计算数据彼此吻合得很好。
We present density-functional calculations of a monolayer of 3,4,9,10-perylene-tetracarboxylic-dianhydride adsorbed on the Ag(111) surface, yielding detailed insight into the structural and electronic properties of this prototypical adsorption system. Using the local-density approximation as the best choice for the exchange-correlation functional, we discuss the bond lengths inside the molecules, the distortion of the molecules due to adsorption, and their position and orientation relative to the substrate and to each other. Based on the calculated geometric and electronic structures, we calculate scanning tunneling microscopy and spectroscopy data within the Tersoff-Hamann framework [Phys. Rev. B. 31, 805 (1985)]. To this end, two-dimensional Fourier transform methods and spatial extrapolation techniques are employed to evaluate the sample wave functions at the tip position. We obtain constant-current images and spectral data that reveal detailed information about the electronic structure of the system. In addition, we have measured the same data by low-temperature scanning tunneling microscopy and scanning tunneling spectroscopy. Our measured and calculated data are in good agreement with one another.