Nat. Commun.: Symmetry Breakdown of 4,4″-Diamino-p-Terphenyl on A Cu(111) Surface by Lattice Mismatch

Title：

Symmetry Breakdown of 4,4″-Diamino-p-Terphenyl on A Cu(111) Surface by Lattice Mismatch

Authors：

Qigang Zhong¹, Daniel Ebeling^2,*, Jalmar Tschakert², Yixuan Gao³, Deliang Bao³, Shixuan Du^3,*, Chen Li⁴,   Lifeng Chi^1,* & André Schirmeisen²

Institutions：

¹Institute of Functional Nano & Soft Materials (FUNSOM), Jiangsu Key Laboratory for Carbon-Based Functional Materials and Devices, Soochow University, Suzhou 215123, P. R. China.

²Institute of Applied Physics, Justus-Liebig University, Heinrich-Buff-Ring 16, 35392 Giessen, Germany.

³Institute of Physics & University of Chinese Academy of Sciences, Chinese Academy of Sciences, Beijing 100190, P. R. China.

⁴School of Environment and Civil Engineering, Dongguan University of Technology, Dongguan 523808, P. R. China.

Abstract：

Site-selective functionalization of only one of two identical chemical groups within one molecule is highly challenging, which hinders the production of complex organic macromolecules. Here we demonstrate that adsorption of 4,4″-diamino-p-terphenyl on a metal surface leads to a dissymmetric binding affinity. With low temperature atomic force microscopy, using CO-tip functionalization, we reveal the asymmetric adsorption geometries of 4,4″-diamino-p-terphenyl on Cu(111), while on Au(111) the symmetry is retained. This symmetry breaking on Cu(111) is caused by a lattice mismatch and interactions with the subsurface atomic layer. The dissymmetry results in a change of the binding affinity of one of the amine   groups, leading to a non-stationary behavior under the influence of the   scanning tip. Finally, we exploit this dissymmetric binding affinity for on-surface self-assembly with 4,4″-diamino-p-terphenyl for side-preferential attachment of 2-triphenylenecarbaldehyde. Our findings provide a new route towards surface-induced dissymmetric activation of a symmetric compound.

IF：

12.353

Link：

https://www.nature.com/articles/s41467-018-05719-y