在大气条件下,利用扫描隧道显微镜研究了四个β-联碳酰基类衍生物在高定向裂解石墨(HOPG)表面的自组装结构.研究分子的结构中均包含π电子共轭体系和烷基链.实验研究了分子结构对自组装结构的影响,并利用分子结构的变化实现了自组装膜结构的调控.结果表明,在甲苯溶剂中制备的这些自组装结构均长程有序,分子间氢键和偶极相互作用是影响自组装膜结构变化的重要因素.
The adsorption of four β-dicarbonyl derivatives on highly oriented pyrolytic graphite(HOPG) surface was studied by scanning tunneling microscopy (STM) in an ambient environment. All the molecules include π-conjugated part and alkyl chains in their chemical structures. The molecules were dissolved in toluene and a drop of the solution was deposited on HOPG to form self-assembled adlayer. The characteristic stripe-like structure in the self-assembled monolayer (SAM) on the high-resolution STM images of the compounds was observed. Different molecular structures led to different SAMs. It was found that noncovalent interactions such as hydrogen bonds and dipole-dipole interactions played an important role in the formation of different SAMs.