University of Oulu

Abdul Rahman Abid et al 2020 J. Phys. B: At. Mol. Opt. Phys. 53, 244001,

Electron–ion coincidence spectroscopy of a large organic molecule : photofragmentation of avobenzone after valence and core ionisation

Saved in:
Author: Abid, Abdul Rahman1; Pelimanni, Eetu1; Reinhardt, Maximilian1;
Organizations: 1Nano and Molecular Systems Research Unit, University of Oulu, Finland
2MAX IV Laboratory, Lund University, Sweden
3Molecular and Condensed Matter Physics, Uppsala University, Sweden
Format: article
Version: published version
Access: open
Online Access: PDF Full Text (PDF, 3.1 MB)
Persistent link:
Language: English
Published: IOP Publishing, 2020
Publish Date: 2020-11-25


The Avobenzone (AVOB) molecule is very photoactive and undergoes irreversible degradation upon irradiation. We studied its valence and core-level (C1s and O1s) photoionisation and subsequent photofragmentation with photoelectron spectroscopy and photoelectron–photoion–photoion coincidence (PEPIPICO) spectroscopy. AVOB is one of the largest molecules studied with this technique. The results show that the AVOB molecule dissociates into an extensive range of fragments by different pathways with little element or site-selectivity. The coincident maps were used to determine selected fragment separation sequences by analysing the slopes of patterns from ion pairs after the core ionisation. Charge delocalisation over the benzene rings and their relative stability favor fragmentation by cleavage of the bridge between them.

see all

Series: Journal of physics. B, Atomic, molecular and optical physics
ISSN: 0953-4075
ISSN-E: 1361-6455
ISSN-L: 0953-4075
Volume: 53
Issue: 24
Article number: 244001
DOI: 10.1088/1361-6455/abc228
Type of Publication: A1 Journal article – refereed
Field of Science: 114 Physical sciences
Funding: The research leading to these results has been supported by the European Union's Horizon 2020 Research and Innovation Programme under the Marie Skłodowska-Curie I4Future (Grant agreement No. 713606). This project was also granted travel funding from CALIPSOPlus from the EU Framework Programme for Research and Innovation Horizon 2020 (Grant agreement No. 730872) and the Magnus Ehrnrooth Foundation, Finland. MR, MP, EP, and MH acknowledge the Academy of Finland funding. EP further acknowledges the financial support from the Finnish Cultural Foundation. OB acknowledges funding from the Swedish Research Council (VR) for the project VR 2017-04162. We thank Prof. E Kukk for the help with the coincidence setup, Dr. A Czasch for the help with the CoboldPC software, and Drs. R Pärna and K Chernenko for the assistance during the experiments. We acknowledge MAX IV Laboratory for time on Beamline FinEstBeAMS under Proposal 20180430. Research conducted at MAX IV, a Swedish national user facility, is supported by the Swedish Research council under contract 2018-07152, the Swedish Governmental Agency for Innovation Systems under contract 2018-04969, and Formas under contract 2019-02496.
EU Grant Number: (713606) I4FUTURE - Novel Imaging and Characterisation Methods in Bio, Medical, and Environmental Research and Technology Innovations
Copyright information: © 2020 The Author(s). Published by IOP Publishing Ltd. Original content from this work may be used under the terms of the Creative Commons Attribution 4.0 licence. Any further distribution of this work must maintain attribution to the author(s) and the title of the work, journal citation and DOI.