Empa, Swiss Federal Laboratories for materials testing and research, Feuerwerkerstrasse 39, 3602 Thun, Switzerland.
Nanoscale. 2010 Apr;2(4):502-8. doi: 10.1039/b9nr00431a. Epub 2010 Mar 19.
Surface-supported molecular self-assembly with the goal to produce highly ordered, functional supramolecular nanostructures are often realized using nanopatterned surfaces, which exhibit long range - ideally periodic - modulations of the molecule adsorption properties. To elucidate the physical origins of the site-specific adsorption properties of such a nanopatterned substrate, we investigated the temperature-dependent microscopic structure and the dynamics of adsorbed Xe at different temperatures on single-sheet h-BN on a Rh(111) nanomesh. In combination with molecular dynamics simulations we show that the site-specific adsorption arises from two different interactions of similar magnitude with respect to their lateral variations. The first can be attributed to a van der Waals type interaction, whereas the second originates from lateral variation of the electrostatic surface potential and is of polarization type. Both types lead to an adsorption energy minimum at the rim of the nanomesh pore and are therefore responsible for stabilizing dynamic and static Xe rings in these pores. The insight into this interplay of interactions should pave the way to gain a more general knowledge on such site-specific adsorption processes.
采用具有长程（理想的周期性）调制分子吸附性质的纳米图案表面，实现了以产生高度有序、功能的超分子纳米结构为目标的表面支撑分子自组装。为了阐明这种纳米图案基底的特定位置吸附性质的物理起源，我们研究了在 Rh(111)纳米网格上单层 h-BN 上不同温度下吸附 Xe 的温度依赖性微观结构和动力学。结合分子动力学模拟，我们表明，特定位置的吸附源于两种具有相似大小的不同相互作用，相对于它们的横向变化。第一种可以归因于范德华类型的相互作用，而第二种则源于静电表面电势的横向变化，并且是极化类型的。这两种类型都在纳米网格孔的边缘处导致吸附能最小，因此负责稳定这些孔中的动态和静态 Xe 环。对这种相互作用的深入了解应该为获得关于这种特定位置吸附过程的更普遍知识铺平道路。
