By the same authors

From the same journal

From the same journal

Observation of Near-Threshold Resonances in the Flavin Chromophore Anions Alloxazine and Lumichrome

Research output: Contribution to journalArticle

Full text download(s)

Published copy (DOI)

Author(s)

Department/unit(s)

Publication details

JournalJOURNAL OF PHYSICAL CHEMISTRY LETTERS
DateAccepted/In press - 2 Oct 2018
DatePublished (current) - 2 Oct 2018
Issue number20
Volume9
Number of pages7
Pages (from-to)6124-6130
Original languageEnglish

Abstract

Lumichrome (LC) is the chromophore of the flavin family of photoactive biomolecules, where key biochemical activity involves interplay between redox and photophysical events. Questions remain about the relationship between the redox status of the ground and excited states and demand an improved understanding of the intrinsic photochemistry. Using anion photodissociation spectroscopy, we have measured the intrinsic electronic spectroscopy (564-220 nm) and accompanying photodegradation pathways of the deprotonated anionic form of LC. Experiments were also performed on alloxazine (AL), which is equivalent to LC minus two methyl groups. We observe a resonance state close to 3.8 eV for both anions for the first time, which we tentatively assign to dipole-bound excited states. For AL this state is sufficiently long-lived to facilitate dissociative electron attachment. Our results suggest that the presence of methyl group rotors at key positions along the molecular dipole may reduce the lifetime of the resonance state and hence provide a structural barrier to valence electron capture, and ensuing molecular dissociation.

Bibliographical note

© 2018 American Chemical Society. This is an author-produced version of the published paper. Uploaded in accordance with the publisher’s self-archiving policy. Further copying may not be permitted; contact the publisher for details.

Discover related content

Find related publications, people, projects, datasets and more using interactive charts.

View graph of relations