Milde P, Zerweck U, Eng L M, Abel M, Giovanelli L, Nony L, Mossoyan M, Porte L, Loppacher Ch
Institute of Applied Photophysics, Technische Universität Dresden, D-01062 Dresden, Germany.
Nanotechnology. 2008 Jul 30;19(30):305501. doi: 10.1088/0957-4484/19/30/305501. Epub 2008 Jun 16.
Recently, we investigated the adsorption of octachloro zinc phthalocyanine (ZnPcCl(8)) on Ag(111) by scanning tunneling microscopy. Compared to the standard phthalocyanine, halogenated phthalocyanine molecules show a much more complex binding behavior, which results in the formation of three different structural phases. These phases follow from the ordering process with the formation of 8, 4 and 0 intermolecular hydrogen-halogen bonds (Abel et al 2006 ChemPhysChem 7 82). In the present work we investigate these phases by Kelvin probe force microscopy in order to quantitatively deduce the electric interface barrier of the first monolayer. Our measurements reveal that the binding behavior does not only affect the structural ordering but also the interface dipole formation, which leads to different work functions. The fact that we observe interface barriers of opposite signs between ordered and disordered molecular layers underlines the importance of exactly knowing the molecular arrangement at the interface when assembling organic molecule devices.
最近，我们通过扫描隧道显微镜研究了八氯锌酞菁（ZnPcCl₈）在Ag(111)上的吸附情况。与标准酞菁相比，卤代酞菁分子表现出更为复杂的结合行为，这导致形成了三种不同的结构相。这些相源于有序化过程中形成的8个、4个和0个分子间氢卤键（阿贝尔等人，2006年，《化物理化》7卷，82页）。在本工作中，我们通过开尔文探针力显微镜研究这些相，以便定量推导第一单层的电界面势垒。我们的测量结果表明，结合行为不仅影响结构有序性，还影响界面偶极子的形成，这导致了不同的功函数。我们观察到有序和无序分子层之间存在相反符号的界面势垒，这一事实强调了在组装有机分子器件时准确了解界面分子排列的重要性。
