X-Ray Photoelectron Spectroscopy of Porphycenes: Charge Asymmetry Across Low-Barrier Hydrogen Bonds
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.
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 authorThis 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.
Abstract
Es ist ironisch, dass die Röntgen-Photoelektronenspektroskopie zum empfindlichen Nachweis für starke Wasserstoffbrückenbindungen (low-barrier hydrogen bonds) in Tetrapyrrolen dienen kann, obwohl mit ihr normalerweise alle Elemente außer Wasserstoff nachweisbar sind. Die Stickstoff-1s-Peaks (siehe Diagramm) fallen nie zusammen, nicht einmal, wenn die N⋅⋅⋅H⋅⋅⋅N-Wasserstoffbrücken nahezu ideal symmetrisch sind wie im Fall von Dibenzo[cde,mno]porphycenen.
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