Institut für Theoretische Physik und Astrophysik, Christian-Albrechts-Universität zu Kiel, D-24098 Kiel, Germany.
Institut für Experimentelle und Angewandte Physik, Christian-Albrechts-Universität zu Kiel, D-24098 Kiel, Germany.
Nano Lett. 2015 Aug 12;15(8):5156-60. doi: 10.1021/acs.nanolett.5b01383. Epub 2015 Aug 3.
Sn-phthalocyanine adsorbs on Ag(111) in a physisorbed or a chemisorbed configuration. Both structures are contacted with the tip of a combined scanning tunneling and atomic force microscope. The tunneling conductances of both configurations exhibit similar exponential variations with the tip-molecule distance. The short-range forces, however, display nontrivial distance dependencies. First-principles calculations reproduce the experimental results. Both attractive and repulsive interactions occur between the tip and different parts of the molecule due to a combination of bond formation and electrostatic interactions with the tip electric dipole. Consequently, deformations occur and the force varies in the resulting unexpected fashion.
锡酞菁以物理吸附或化学吸附的形式吸附在 Ag(111)表面。这两种结构都用扫描隧道和原子力显微镜的针尖来接触。这两种构型的隧道电导都随针尖-分子距离表现出相似的指数变化。然而，短程力显示出非平凡的距离依赖性。第一性原理计算再现了实验结果。由于键的形成以及与针尖电偶极子的静电相互作用的结合，针尖和分子的不同部分之间会发生吸引和排斥相互作用。因此，会发生变形，力会以意想不到的方式变化。
