The electronic transitions of molecular oxygen – How to measure and manipulate highly forbidden optical transitions

PhD defence, Thursday June 1st 2017. Mikkel Bregnhøj.

2017.06.01 | Karen Konradi

Mikkel Bregnhøj

During his studies, Mikkel Bregnhøj has investigated the interaction between light, molecular oxygen (O2), and liquids. These three things are highly abundant on this planet and humans need them to survive. Transitions between the electronic states of O2 are “forbidden” by the rules of quantum mechanics. As such, interactions between O2 and light are very improbable. Nevertheless, Mikkel Bregnhøj has studied how interactions with the surrounding molecules (e.g. in a solution) can partially lift this prohibition, allowing O2 and light to interact.

This research has led to the development of new ways to produce the excited electronic states of O2. These, in turn, can be used to study the action of molecular oxygen in solution and in living cells. From a fundamental perspective, this research has contributed to our understanding of the mutual interaction between light, excited electronic states of molecules, and the surrounding environment.

The PhD degree was completed at the Department of Chemistry, Science and Technology, Aarhus University.

This résumé was prepared by the PhD student.


Time: Thursday June 1st 2017 at 12.30
Place: Building 1510, room 213, Auditorium VI, Department of Chemistry, Aarhus University
Title of dissertation: The Electronic Transitions of Molecular Oxygen
Contact information: Mikkel Bregnhøj, e-mail:, phone: +45 28498529
Members of the assessment committee:
Professor Eric Vauthey, Physical Chemistry Department, University of Geneva, Switzerland
Professor Hans Ågren, Department of Theoretical Chemistry and Biology, Royal Institute of Technology, Stockholm, Sweden
Professor Henrik Stapelfeldt (Chairman), Department of Chemistry, Aarhus University
Main supervisor:
Professor Peter R. Ogilby, Department of Chemistry, Aarhus University
Language: The PhD dissertation will be defended in English

The defence is public.
The dissertation is available for reading at the Graduate School of Science and Technology/GSST, Ny Munkegade 120, building 1520, rooms 128-134, 8000 Aarhus C.

PhD defence
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Revised 19.05.2017