Temperature dependence of conformation, chemical state, and metal-directed assembly of tetrapyridyl-porphyrin on Cu(111)

Journal Article · Sun Dec 07 00:00:00 EST 2008 · Journal of Chemical Physics

DOI:https://doi.org/10.1063/1.3021291· OSTI ID:21254939

Klappenberger, F; Auwaerter, W; Marschall, M ^[1]; Weber-Bargioni, A ^[2]; Schiffrin, A ^[3]; Barth, J V ^[2]

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1. Physik Department E20, Technische Universitaet Muenchen, James-Franck Str., D-85748 Garching (Germany)
2. Department of Physics and Astronomy, University of British Columbia, AMPEL 2355 East Mall, Vancouver V6T 1Z4 (Canada)
3. Department of Chemistry, University of British Columbia, AMPEL 2355 East Mall, Vancouver V6T 1Z4 (Canada)

We present a combined scanning tunneling microscopy (STM), near-edge x-ray-absorption fine-structure, and x-ray photoemission spectroscopy (XPS) study on the bonding and ordering of tetrapyridyl-porphyrin molecules on the Cu(111) surface in the 300-500 K temperature range. Following deposition at 300 K the molecules are adsorbed with a pronounced conformational adaptation of the anchored species featuring a saddle-shaped macrocycle and terminal groups pointing toward the substrate. Upon moderate annealing supramolecular chains evolve that are stabilized by metal-ligand interactions between the mesopyridyl substituents and copper adatoms resulting in twofold copper coordination. Annealing to temperatures exceeding 450 K strongly alters the molecular appearance in high-resolution STM data. This modification was also induced by controlled voltage pulses and related to a deprotonation of the molecule by XPS. Under appropriate conditions a novel binding motif leads to honeycomb structures coexisting with the chain segments. The conformation withstands annealing without large modification.

• OSTI ID: 21254939
• Journal Information: Journal of Chemical Physics, Vol. 129, Issue 21; Other Information: DOI: 10.1063/1.3021291; (c) 2008 American Institute of Physics; Country of input: International Atomic Energy Agency (IAEA); ISSN 0021-9606
• Country of Publication: United States
• Language: English

Related Subjects

37 INORGANIC
ORGANIC
PHYSICAL AND ANALYTICAL CHEMISTRY
36 MATERIALS SCIENCE
ABSORPTION
ABSORPTION SPECTROSCOPY
ADSORPTION
ANNEALING
CHEMICAL STATE
COPPER
DISSOCIATION
HONEYCOMB STRUCTURES
MODIFICATIONS
MOLECULAR STRUCTURE
PHOTOEMISSION
PORPHYRINS
SCANNING TUNNELING MICROSCOPY
TEMPERATURE DEPENDENCE
TEMPERATURE RANGE 0273-0400 K
TEMPERATURE RANGE 0400-1000 K
X RADIATION
X-RAY PHOTOELECTRON SPECTROSCOPY
X-RAY SPECTROSCOPY