title: Length effects in VUV photofragmentation of protonated peptides.
abstract: We have studied photoionization of protonated synthetic peptides YG(n)F (n = 0, 1, 3, 5, 10). Photon energies ranging from 8 to 30 eV were used. For YG(n)F peptides up to n = 5 small fragment ions related to the sidechains of the aromatic terminal amino acids Y and F dominate the fragmentation patterns. The associated yields scale with total photoabsorption cross section, demonstrating efficient hole migration towards the terminal amino acids upon photoionization of the peptide backbone. For n = 10 the side-chain loss channel is quenched and a series of large dications appear.
authors.affiliation: KVI Atomic and Molecular Physics, University of Groningen, The Netherlands.
authors.forename: O
authors.initials: O
authors.lastname: González-Magaña
authors.forename: G
authors.initials: G
authors.lastname: Reitsma
authors.forename: S
authors.initials: S
authors.lastname: Bari
authors.forename: R
authors.initials: R
authors.lastname: Hoekstra
authors.forename: T
authors.initials: T
authors.lastname: Schlathölter
mesh_terms: D000596:Amino Acids / Q000737:chemistry; D013058:Mass Spectrometry; D010455:Peptides / Q000138:chemical synthesis / Q000737:chemistry*; D055668:Photochemical Processes; D011522:Protons; D014466:Ultraviolet Rays; D014618:Vacuum
chemical_list: D000596:Amino Acids; D010455:Peptides; D011522:Protons