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Darstellung und Charakterisierung atmosphaerenrelevanter Fluorverbindungen - Synthesis and Characterization of Fluorine Compounds of atmospheric Relevance

The present study is a contribution to the synthesis and extensive characterization of fundamental C, F, O containing compounds, which play an important role in the chemistry of the atmosphere due to their appearance in degradation processes of CFCs and their substitutes. The formation of the peroxy radicals CF3OO, FC(O)OO, CF3OC(O)OO, CF3C(O)OO, and CH3C(O)OO is achieved by low pressure thermolysis of suitable precursors, highly diluted in argon or neon and subsequent quenching of the reaction mixture as a matrix. In addition, the radicals CF3OCO, SF5, and CF3OOO are formed in matrix. All investigated radicals are characterized as matrix isolated species by IR- and UV-spectroscopy. The properties of the studied fluorocarbon peroxy radicals are comprehensively discussed. The first preparation of pure trifluoromethyl nitrate, CF3ONO2, is reported via different synthetic routes. The compound is completely characterized (IR, Raman, UV, NMR, melting and boiling point, vapour pressure, gas electron diffraction), a nd its chemistry is evaluated. It is demonstrated, that trifluoromethyl nitrate acts neither for CF3O radicals, nor for nitrogen dioxide as a reservoir species. With the synthesis of bistrifluoromethyl trioxydicarbonate, CF3OC(O)OO-OC(O)OCF3, a novel open-chain trioxide is obtained, which is thermally stable below -20°C. CF3OC(O)OOOC(O)OCF3 is characterized by IR, Raman, UV, NMR spectroscopy and is used in the generation of the previously unknown peroxy radical CF3OC(O)OO. For all investigated species quantum chemical calculations are performed. The consistent use of the density functional method B3LYP with the basis set 6-311G(d,p) allows a comprehensive theoretical study. In addition, band assignments of the spectra of the characterized compounds were supported by these calculations.

Identiferoai:union.ndltd.org:DUETT/oai:DUETT:duett-06202003-094854
Date20 June 2003
CreatorsAhsen, Stefan von
ContributorsProf. Dr. H. Willner, Prof. Dr. H.-J. Frohn
PublisherGerhard-Mercator-Universitaet Duisburg
Source SetsDissertations and other Documents of the Gerhard-Mercator-University Duisburg
LanguageGerman
Detected LanguageEnglish
Typetext
Formattext/html, application/pdf
Sourcehttp://www.ub.uni-duisburg.de/ETD-db/theses/available/duett-06202003-094854/
Rightsunrestricted, I hereby certify that, if appropriate, I have obtained and attached hereto a written permission statement from the owner(s) of each third party copyrighted matter to be included in my thesis, dissertation, or project report, allowing distribution as specified below. I certify that the version I submitted is the same as that approved by my advisory committee. Hiermit erteile ich der Universitaet Duisburg das nicht-ausschliessliche Recht unter den unten angegebenen Bedingungen, meine Dissertation, Staatsexamens- oder Diplomarbeit, meinen Forschungs- oder Projektbericht zu veroeffentlichen und zu archivieren. Ich behalte das Urheberrecht und das Recht das Dokument zu veroeffentlichen und in anderen Arbeiten weiterzuverwenden.

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