TY - JOUR
T1 - Sticking with the Pointy End? Molecular Configuration of Chloro Boron-Subphthalocyanine on Cu(111)
AU - Ilyas, Nahid
AU - Harivyasi, Shashank S.
AU - Zahl, Percy
AU - Cortes, Rocio
AU - Hofmann, Oliver T.
AU - Sutter, Peter
AU - Zojer, Egbert
AU - Monti, Oliver L.A.
N1 - Funding Information:
The authors thank Leonhard Grill (University of Graz), Elisabeth Wruss, and Elisabeth Verw?ster (TU Graz) for stimulating discussions. This research was supported by the National Science Foundation under Grant CHE-1213243 (Arizona), by the European Union Seventh Framework Programme under grant agreement no 607232 [THINFACE] and by the Austrian Science Fund (FWF), P24666-N20. This research also used resources of the Center for Functional Nanomaterials, which is a U.S. DOE Office of Science Facility, at Brookhaven National Laboratory under Contract No. DESC0012704. The computational results presented have been achieved using the Vienna Scientific Cluster (VSC). We would also like to thank Dr. Bj?rn Lange and Prof. Volker Blum at Duke University for making their new implementation of STM simulations in FHI-aims available to us.
PY - 2016/4/7
Y1 - 2016/4/7
N2 - In this combined low-temperature scanning tunneling microscopy (STM) and density functional theory (DFT) study, we investigate self-assembly of the dipolar nonplanar organic semiconductor chloro boron-subphthalocyanine (ClB-SubPc) on Cu(111). We observe multiple distinct adsorption configurations and demonstrate that these can only be understood by taking surface-catalyzed dechlorination into account. A detailed investigation of possible adsorption configurations and the comparison of experimental and computational STM images demonstrates that the configurations correspond to "Cl-up" molecules with the B-Cl moiety pointing toward the vacuum side of the interface, and dechlorinated molecules. In contrast to the standard interpretation of adsorption of nonplanar molecules in the phthalocyanine family, we find no evidence for "Cl-down" molecules where the B-Cl moiety would be pointing toward the Cu surface. We show computationally that such a configuration is unstable and thus is highly unlikely to occur for ClB-SubPc on Cu(111). Using these assignments, we discuss the different self-assembly motifs in the submonolayer coverage regime. The combination of DFT and STM is essential to gain a full atomistic understanding of the surface-molecule interactions, and our findings imply that phthalocyanines may undergo surface-catalyzed reactions hitherto not considered. Our results also indicate that care has to be taken when analyzing possible adsorption configurations of polar members of the phthalocyanine family, especially when they are adsorbed on comparably reactive surfaces like Cu(111). (Figure Presented).
AB - In this combined low-temperature scanning tunneling microscopy (STM) and density functional theory (DFT) study, we investigate self-assembly of the dipolar nonplanar organic semiconductor chloro boron-subphthalocyanine (ClB-SubPc) on Cu(111). We observe multiple distinct adsorption configurations and demonstrate that these can only be understood by taking surface-catalyzed dechlorination into account. A detailed investigation of possible adsorption configurations and the comparison of experimental and computational STM images demonstrates that the configurations correspond to "Cl-up" molecules with the B-Cl moiety pointing toward the vacuum side of the interface, and dechlorinated molecules. In contrast to the standard interpretation of adsorption of nonplanar molecules in the phthalocyanine family, we find no evidence for "Cl-down" molecules where the B-Cl moiety would be pointing toward the Cu surface. We show computationally that such a configuration is unstable and thus is highly unlikely to occur for ClB-SubPc on Cu(111). Using these assignments, we discuss the different self-assembly motifs in the submonolayer coverage regime. The combination of DFT and STM is essential to gain a full atomistic understanding of the surface-molecule interactions, and our findings imply that phthalocyanines may undergo surface-catalyzed reactions hitherto not considered. Our results also indicate that care has to be taken when analyzing possible adsorption configurations of polar members of the phthalocyanine family, especially when they are adsorbed on comparably reactive surfaces like Cu(111). (Figure Presented).
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U2 - 10.1021/acs.jpcc.5b11799
DO - 10.1021/acs.jpcc.5b11799
M3 - Article
AN - SCOPUS:84964337080
VL - 120
SP - 7113
EP - 7121
JO - Journal of Physical Chemistry C
JF - Journal of Physical Chemistry C
SN - 1932-7447
IS - 13
ER -