Feng, Zhijing and Velari, Simone and Dri, Carlo and Goldoni, Andrea and Patera, Laerte L. and Regeni, Irene and Forzato, Cristina and Berti, Federico and Peressi, Maria and De Vita, Alessandro and Comelli, Giovanni (2019) Bifunctional Behavior of a Porphyrin in Hydrogen-Bonded Donor-Acceptor Molecular Chains on a Gold Surface. JOURNAL OF PHYSICAL CHEMISTRY C, 123 (12). pp. 7088-7096. ISSN 1932-7447,
Full text not available from this repository. (Request a copy)Abstract
Peculiar hydrogen-bonded molecular chains are spontaneously created from the self-assembly on a gold surface of a porphyrin functionalized with four aromatic amine moieties. The molecular chains are formed by a sequence of dyads, where the same molecule behaves alternately as a hydrogen-bond acceptor or donor as a whole at all its four aromatic amino groups. This remarkable bifunctional behavior is due to the conformational flexibility of the functionalizing amino groups that switch from a planar, aniline-like conformation in donors to a pyramidal, amine-like one in acceptors. Furthermore, we show that the acceptor porphyrins can trap gold adatoms underneath their center. Combined scanning tunneling microscopy experiments and density functional theory calculations characterize the structural and electronic modifications suffered by such molecules to establish amino-amino interactions. Notably, scanning tunneling spectroscopy measurements show that the highest occupied molecular orbital-lowest unoccupied molecular orbital gaps of the acceptors and donors are, respectively, larger and smaller with respect to the isolated molecule according to the reduced extent of conjugation occurring in the acceptors. In summary, experimental and theoretical results reveal a remarkable hydrogen-bonded complex where the amino groups act as both hydrogen-bond donors and acceptors and suggest how hydrogen bonding can modify the geometrical and potentially also the electronic structures of highly conjugated molecules.
| Item Type: | Article |
|---|---|
| Uncontrolled Keywords: | JUNCTION CONDUCTANCE; AU(111) SURFACE; CHARGE-TRANSFER; METALATION; COORDINATION; ADSORPTION; 2H-TETRAPHENYLPORPHYRIN; TETRAPHENYLPORPHYRIN; DEHYDROGENATION; CONFORMATION; |
| Subjects: | 500 Science > 530 Physics |
| Divisions: | Physics > Institute of Experimental and Applied Physics Physics > Institute of Experimental and Applied Physics > Chair Professor Giessibl > Group Jascha Repp |
| Depositing User: | Dr. Gernot Deinzer |
| Date Deposited: | 15 Apr 2020 10:27 |
| Last Modified: | 15 Apr 2020 10:27 |
| URI: | https://pred.uni-regensburg.de/id/eprint/27330 |
Actions (login required)
 |
View Item |
