Chiral Self-Assembly of Nonplanar 10,10′-Dibromo-9,9′-bianthryl
Molecules on Ag(111)
Yixian Shen
Guo Tian
Han Huang
Yanwei He
Qiliang Xie
Fei Song
Yunhao Lu
Pingshan Wang
Yongli Gao
10.1021/acs.langmuir.7b00218.s001
https://acs.figshare.com/articles/journal_contribution/Chiral_Self-Assembly_of_Nonplanar_10_10_-Dibromo-9_9_-bianthryl_Molecules_on_Ag_111_/4754089
We
report on the low-temperature scanning tunneling microscopy
(STM) measurements of the self-assembly of nonplanar 10,10′-dibromo-9,9′-bianthryl
(DBBA) molecules on Ag(111) combined with density functional theory
(DFT) calculations. DBBA molecules have two enantiomorphous adsorption
configurations, from which more chiral structures can be formed. At
a low coverage [0.4 monolayer (ML)], DBBA forms racemic netlike islands
consisting of molecular chains along ⟨1 2 3̅⟩<sub>Ag</sub>. Moreover, the gliding between the molecular chains gives
rise to chiral windmill-like patterns in the islands. At 0.8 ML, DBBA
forms a racemic row phase and a homochiral hexamer phase. The molecular
appearance difference between the two coexisted phases and the DFT
calculated molecular adsorption configuration reveal a decrease in
the molecular dihedral angle of DBBA, which implies an enhancement
in the intermolecular interactions via CH···π
and halogen bonds. The transition from a racemic packing mode to a
homochiral one suggests that the suitability of steric configurations
is dominant in the close-packing mode under enhanced intermolecular
interactions.
2017-03-05 00:00:00
chiral windmill-like patterns
coexisted phases
chiral structures
adsorption configuration
close-packing mode
homochiral hexamer phase
racemic row phase
interaction
scanning tunneling microscopy
steric configurations
dihedral angle
Chiral Self-Assembly
CH
DFT
DBBA forms
halogen bonds
appearance difference
0.8 ML
STM
enantiomorphous adsorption configurations
Ag
DBBA molecules