J. Phys. Chem. A 2010, 114, 299–303
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UV Photodissociation of Protonated Gly-Trp and Trp-Gly Dipeptides and Their Complexes with Crown Ether in an Electrostatic Ion Storage Ring Anneli Ehlerding, Jean Ann Wyer, Henning Zettergren, Maj-Britt Suhr Kirketerp, and Steen Brøndsted Nielsen* Department of Physics and Astronomy, Aarhus UniVersity, Ny Munkegade, DK-8000 Aarhus C, Denmark ReceiVed: September 7, 2009; ReVised Manuscript ReceiVed: NoVember 17, 2009
Photodissociation of protonated GW, WG (G ) glycine, W ) tryptophan), and their complexes with 18crown-6-ether (CE) was performed in an electrostatic ion storage ring using a tunable laser system. On the basis of lifetime measurements, action spectra were obtained from 210 to 360 nm. These reveal that whereas [GW + H]+ absorbs maximally at ∼220 nm, the absorption maximum is
