title: Photoelectron spectroscopy of gramicidin polyanions: competition between delayed and direct emission.
abstract: We present the first photoelectron (PE) spectra of polypeptide polyanions. Combining PE spectroscopy and mass spectrometry provides a direct measurement of the stability of the polyanions with respect to electron detachment and of the repulsive energy between excess charges. The second electron affinity of gramicidin was found to amount to 2.35 +/- 0.15 eV, and the value of the repulsive Coulomb barrier was estimated to be 0.5 +/- 0.15 eV. The spectra are interpreted as resulting from a competition between delayed and direct emission.
authors.affiliation: Institut für Physikalische Chemie, Universität Karlsruhe, Kaiserstrasse 12, D-76128 Karlsruhe, Germany.
authors.forename: Katerina
authors.initials: K
authors.lastname: Matheis
authors.forename: Laure
authors.initials: L
authors.lastname: Joly
authors.forename: Rodolphe
authors.initials: R
authors.lastname: Antoine
authors.forename: Franck
authors.initials: F
authors.lastname: Lépine
authors.forename: Christian
authors.initials: C
authors.lastname: Bordas
authors.forename: Oli T
authors.initials: OT
authors.lastname: Ehrler
authors.forename: Abdul-Rahman
authors.initials: AR
authors.lastname: Allouche
authors.forename: Manfred M
authors.initials: MM
authors.lastname: Kappes
authors.forename: Philippe
authors.initials: P
authors.lastname: Dugourd
mesh_terms: D001407:Bacillus / Q000737:chemistry; D004583:Electrons; D006096:Gramicidin / Q000737:chemistry*; D007700:Kinetics; D008958:Models, Molecular; D008968:Molecular Conformation; D000071228:Polyelectrolytes; D011108:Polymers / Q000737:chemistry*; D013057:Spectrum Analysis
chemical_list: D006096:Gramicidin; D000071228:Polyelectrolytes; D011108:Polymers