Communication
X-Ray Photoelectron Spectroscopy of Porphycenes: Charge Asymmetry Across Low-Barrier Hydrogen Bonds
Abhik Ghosh Prof. Dr.,
John Moulder Dr.,
Martin Bröring Dr.,
Emanuel Vogel Prof. Dr.,
Abhik Ghosh Prof. Dr.
Institute of Chemistry University of Tromsø 9037 Tromsø (Norway) Fax: (+47) 77644765
Search for more papers by this authorJohn Moulder Dr.
Physical Electronics, Inc. 6509 Flying Cloud Drive, Eden Prairie, MN 55344 (USA)
Search for more papers by this authorMartin Bröring Dr.
Institut für Anorganische Chemie, Universität Würzburg Am Hubland, 97074 Würzburg (Germany)
Search for more papers by this authorEmanuel Vogel Prof. Dr.
Institut für Organische Chemie der Universität Greinstrasse 4, 50939 Köln (Germany)
Search for more papers by this authorAbhik Ghosh Prof. Dr.,
John Moulder Dr.,
Martin Bröring Dr.,
Emanuel Vogel Prof. Dr.,
Abhik Ghosh Prof. Dr.
Institute of Chemistry University of Tromsø 9037 Tromsø (Norway) Fax: (+47) 77644765
Search for more papers by this authorJohn Moulder Dr.
Physical Electronics, Inc. 6509 Flying Cloud Drive, Eden Prairie, MN 55344 (USA)
Search for more papers by this authorMartin Bröring Dr.
Institut für Anorganische Chemie, Universität Würzburg Am Hubland, 97074 Würzburg (Germany)
Search for more papers by this authorEmanuel Vogel Prof. Dr.
Institut für Organische Chemie der Universität Greinstrasse 4, 50939 Köln (Germany)
Search for more papers by this authorFirst published: 19 January 2001
Citations: 23
This work was supported by the Norwegian Research Council, the VISTA program of Statoil (Norway), the Norwegian Academy of the Sciences and Letters, and the Deutsche Forschungsgemeinschaft. A.G. acknowledges stimulating discussions with Professor Thomas H. Morton.
Graphical Abstract
It is ironic that although it is typically a technique that “sees” all elements other than hydrogen atoms, X-ray photoelectron spectroscopy (XPS) acts as a sensitive probe of low-barrier hydrogen bonds, as seen in a study of free-base tetrapyrroles. The nitrogen 1s XPS peaks never quite coalesce, even when the N⋅⋅⋅H⋅⋅⋅N hydrogen bonds are almost perfectly symmetrical, as is the case for dibenzo[cde,mno]porphycenes (see picture).
References
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