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University of Groningen Chemistry and photophysics of polycyclic aromatic hydrocarbons in the interstellar medium Boschman, Leon

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University of Groningen

Chemistry and photophysics of polycyclic aromatic hydrocarbons in the interstellar medium

Boschman, Leon

IMPORTANT NOTE: You are advised to consult the publisher's version (publisher's PDF) if you wish to cite from it. Please check the document version below.

Document Version

Publisher's PDF, also known as Version of record

Publication date: 2017

Link to publication in University of Groningen/UMCG research database

Citation for published version (APA):

Boschman, L. (2017). Chemistry and photophysics of polycyclic aromatic hydrocarbons in the interstellar medium. Rijksuniversiteit Groningen.

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Stellingen

behorende bij het proefschrift

Chemistry and Photophysics of

Polycyclic Aromatic Hydrocarbons

in the Interstellar Medium

1. De superhydrogenatie van ge¨ıoniseerd coroneen is aan alternerende barri`eres onderhevig. (Hoofdstuk 3)

2. Ge¨ıoniseerd coroneen met 5, 11, of 17 extra waterstofatomen is stabieler dan ge¨ıoniseerd coroneen met een ander aantal waterstofatomen. (Hoofdstuk 4) 3. De fragmentatiekanalen na absorptie van een ultraviolet foton door een ge¨ıoniseerd

coroneenmolecuul veranderen drastisch na additie van een waterstofatoom. (Hoofdstuk 5)

4. Polycyclische aromatische koolwaterstoffen leveren een belangrijke bijdrage aan de vorming van moleculair waterstof in photodissociation regions. (Hoofd-stuk 6)

5. Stellingen zijn er om te prikkelen en tot nadenken uit te dagen, niet om de lezer te vermaken en behagen.

6. Wetenschappers dienen zich bewust te zijn van hun bevoorrechte positie. 7. Het gouden tijdperk van wetenschappelijke vooruitgang is nu.

8. Menselijk gedrag is zelden rationeel, maar bijna altijd logisch verklaarbaar. 9. Het is belangrijker om een goed experiment te doen dan een perfecte opstelling

te bouwen.

10. De fundamentele wetenschap en het bedrijfsleven kunnen niet zonder elkaar en het wordt tijd dat beide werelden dit erkennen.

L.M.P.V. Boschman November 2016, Groningen

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Propositions

accompanying the dissertation

Chemistry and Photophysics of

Polycyclic Aromatic Hydrocarbons

in the Interstellar Medium

1. The superhydrogenation of ionized coronene is subject to alternating barriers. (Chapter 3)

2. Ionized coronene with 5, 11, or 17 additional hydrogen atoms is more stable than ionized coronene with a different number of additional hydrogen atoms. (Chapter 4)

3. The fragmentation pathways upon absorption of an ultraviolet photon by an ionized coronene molecule change drastically after the addition of a hydrogen atom. (Chapter 5)

4. Polycyclic aromatic hydrocarbons make an important catalytic contribution to the formation of molecular hydrogen in photodissociation regions. (Chapter 6)

5. The function of a proposition is to provoke the reader and challenge them to think, not just to please and entertain.

6. Scientists should be aware of their privileged position. 7. The golden age of scientific progress is now.

8. Human behaviour is seldom rational, but almost always logically explicable. 9. It is more important to perform a good experiment than to build a perfect

setup.

10. Fundamental science and the private sector cannot exist without each other, and it is about time that both worlds acknowledge this.

L.M.P.V. Boschman November 2016, Groningen

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