| Autor: |
Xiao, W. D., Zhang, Y. Y., Tao, L., Aït-Mansour, K., Chernichenko, K. Y., Nenajdenko, V. G., Ruffieux, P., Du, S. X., Gao, H.-J., Fasel, R. |
| Předmět: |
|
| Zdroj: |
Scientific Reports; 6/27/2014, p1-6, 6p |
| Abstrakt: |
Despite the development of crystal engineering, it remains a great challenge to predict the crystal structure even for the simplest molecules, and a clear link between molecular and crystal symmetry is missing in general. Here we demonstrate that the two- dimensional (2D) crystallization of heterocirculenes on a Au(111) surface is greatly affected by the molecular symmetry. By means of ultrahigh vacuum scanning tunneling microscopy, we observe a variety of 2D crystalline structures in the coverage range from submonolayer to monolayer for D8h-symmetric sulflower (C16S8), whereas D4h-symmetric selenosulflower (C16S4Se4) forms square and rectangular lattices at submonolayer and monolayer coverages, respectively. No long-range ordered structure is observed for C1h-symmetric selenosulflower (C16S5Se3) self-assembling at submonolayer coverage. Such different self-assembly behaviors for the heterocirculenes with reduced molecular symmetries derive from the tendency toward close packing and the molecular symmetry retention in 2D crystallization due to van der Waals interactions. [ABSTRACT FROM AUTHOR] |
| Databáze: |
Complementary Index |
| Externí odkaz: |
|
