Structural and electron transport investigations of functionalized carboxylic acids on Cu(110)-surfaces: experimental and ab initio studies

我们的目标是从实验和理论上研究羧酸盐-铜(110)界面的结构和电子输运，并利用这些数据建立一个基于通过这些分子的不同电子传输路径的分子装置。利用不同构型的不同取代基的羧酸吸附在铜(110)衬底上，研究其基本几何构型和电子输运性质，从而推断HOMO/LUMO能隙对分子间和分子-衬底耦合的影响。在实验上，我们的目标是将差分电导测量和非弹性隧道光谱与高分辨率的UHV-STM相结合，在一个完全定义的环境中获得羧酸的能级和电子-声子耦合。理论上，我们的目标是结合从头算方法来描述结构和输运性质，推导出预测羧酸结构的理论参数，这些羧酸在两种导电状态下都是稳定的，因此它们有可能作为电子器件使用。此外，我们打算对羧酸单层进行化学修饰或原位嵌入单分子，并开发另一种工具来创建电子设备的新结构。最后，我们将利用羧酸分子间相互作用的电子传递来调节垂直于分子的电子传递，从而建立一个分子装置。

Our aim is to investigate the structure and the electronic transport through the carboxylate-Cu(110) interface, experimentally and theoretically, and to use these data to build up a molecular device, which is based on the exploitation of the different electron transport paths through these molecules. Basic geometries and electron transport properties will be investigated using the carboxylic acids with systematically varying substituents adsorbed in different configurations on the Cu(110)-substrate to deduce the influence of the HOMO/LUMO gap on the intermolecular and molecule-substrate coupling. Experimentally we aim to combine differential conductance measurements and inelastic tunneling spectroscopy with high resolution UHV-STM to get the energy levels and the electron-phonon coupling of the carboxylic acids in a thoroughly defined environment. Theoretically we aim at combining ab initio methods to describe structural and transport properties to deduce the theoretical parameters to predict structures of carboxylic acids, which are stable in two conductive states so that they have the potential to be used as electronic devices. Furthermore we intend to chemically modify the carboxylic monolayers or embed single molecules in situ and to develop a further tool to create new structures for electronic devices. Finally we will use the electron transport through the intermolecular ¿-¿ interaction of carboxylic acids to modulate the electron transport vertical through the molecule and to build up a molecular device.