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Updated: May 20, 2026

Self-assembling Morphologies Obtained from Helical Polycarbodiimide Copolymers and Their Triazole Derivatives
Published on: February 7, 2017
Polymorphism in self-assembled structures of 9-anthracene carboxylic acid on Ag(111)
Chao Lu1, Yinying Wei2, Erkuang Zhu1
1State Key Laboratory of Metastable Material Science and Technology, Yanshan University, Qinhuangdao 066004, Hebei, China.
Abstract:
Surface self-assembly process of 9-anthracene carboxylic acid (AnCA) on Ag(111) was investigated using STM. Depending on the molecular surface density, four spontaneously formed and one annealed AnCA ordered phases were observed, namely a straight belt phase, a zigzag double-belt phase, two simpler dimer phases, and a kagome phase. The two high-density belt phases possess large unit cells on the scale length of 10 nm, which are seldom observed in molecular self-assembled structures. This structural diversity stems from a complicated competition of different interactions of AnCA molecules on metal surface, including intermolecular and molecular-substrate interactions, as well as the steric demand from high molecular surface density.
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