Zangmeister Christopher D, Robey Steven W, van Zee Roger D, Yao Yuxing, Tour James M
National Institute of Standards & Technology, Gaithersburg, Maryland 20899, USA.
J Am Chem Soc. 2004 Mar 24;126(11):3420-1. doi: 10.1021/ja0389826.
This communication reports measurement of one-photon (21.2 eV) and one-color, two-photon (3.2-4.5 eV) photoemission spectra of 4,4'-bis-(phenylethynyl)benzenethiol chemisorbed on gold. Four features are observed in these spectra: two occupied, predominantly molecular levels below the Fermi level and two unoccupied, predominantly molecular levels above the Fermi level. The occupied and unoccupied bands closest to the Fermi level are assigned to delocalized pi-bands, and the other occupied and unoccupied bands, to localized pi-bands. With this assignment, the hole- and electron-injection barriers and the transport gap for those levels are deduced.
本通讯报道了吸附在金表面的4,4'-双（苯乙炔基）苯硫醇的单光子（21.2电子伏特）和单色双光子（3.2 - 4.5电子伏特）光电子能谱的测量结果。在这些能谱中观察到四个特征：费米能级以下有两个占据态，主要是分子能级；费米能级以上有两个未占据态，主要也是分子能级。最接近费米能级的占据带和未占据带被归为离域π带，其他的占据带和未占据带则归为定域π带。基于此归属，推导出了这些能级的空穴注入势垒、电子注入势垒和传输能隙。
