Electronic spectroscopy of thiones

Show simple item record

dc.contributor.advisor Brint, Paul en
dc.contributor.author Doherty, William G.
dc.date.accessioned 2014-07-28T11:46:36Z
dc.date.available 2014-07-28T11:46:36Z
dc.date.issued 2003
dc.date.submitted 2003
dc.identifier.citation Doherty, W. G. 2003. Electronic spectroscopy of thiones. PhD Thesis, University College Cork. en
dc.identifier.uri http://hdl.handle.net/10468/1601
dc.description.abstract The phosphorescence excitation spectra of two thiones, 4-H-1-xanthione (XT) and 4-H-1-pyrane-4-thione (PT), cooled in a supersonic jet were investigated. The vibronic lineshape of the T1z origin of PT measured by cavity ring-down spectroscopy is considered and the excited state rotational constants are calculated. For XT the 3A2(nπ* ) → X1A1 phosphorescence excitation spectrum was investigated in the region 14900-17600 cm-1. The structure observed is shown to be due to the T1← S0 absorption and an assignment in terms of the vibronic structure of the band is proposed. A previous assignment of the S1 ← S0 origin is considered and the transition involved is shown to be most probably due to the absorption of a vibronic tiplet state T1z,v7. An alternative but tentative assignment of the S1,0 ←S0,0 transition is suggested. In the case of PT the phosphorescence excitation spectrum was investigated in the region of the 1A2(ππ*) ← X1A1 absorption band between 27300 and 28800 cm-1. The spectrum exhibits complex features which are typical for the strong vibronic coupling case of two adjacent electronic states. The observed intermediate level structure was attributed to the coupling with a lower lying dark electronic state 1B1(nπ*2), whose origin was estimated to be ~ 825 - 1025 cm-1 below the origin of 1A2(ππ*)0. Consequences of the vibronic coupling on the decay dynamics of 1A2(ππ*) as well as tentative assignments of vibronic transitions 1A2(ππ*)v ← X1A1 are also discussed. In the T1z ← S0 cavity ring-down absorption spectrum of PT, the vibronic lineshape of the T1z origin is analysed. As the T1z line is separated from the T1x,1y lines by a large zero-field splitting it is possible to use an Asyrot-like program to calculate the vibrational-rotational parameters determining the lineshape. It is shown that PT is non-planar in the first excited triplet state and the lineshape is composed of a mixture of A-type and C-type bandshapes. The non-planarity of PT is discussed. en
dc.format.mimetype application/pdf en
dc.language.iso en en
dc.publisher University College Cork en
dc.relation.uri http://library.ucc.ie/record=b1360019~S0
dc.rights © 2003, William G. Doherty en
dc.rights.uri http://creativecommons.org/licenses/by-nc-nd/3.0/ en
dc.subject Thiones en
dc.subject Phosphorescence excitation spectra en
dc.subject.lcsh Spectrum analysis en
dc.title Electronic spectroscopy of thiones en
dc.type Doctoral thesis en
dc.type.qualificationlevel Doctoral en
dc.type.qualificationname PhD (Science) en
dc.internal.availability Full text available en
dc.check.info No embargo required en
dc.description.version Accepted Version
dc.description.status Not peer reviewed en
dc.internal.school Chemistry en
dc.check.type No Embargo Required
dc.check.reason No embargo required en
dc.check.opt-out Not applicable en
dc.thesis.opt-out false
dc.check.embargoformat Not applicable en
ucc.workflow.supervisor cora@ucc.ie


Files in this item

This item appears in the following Collection(s)

Show simple item record

© 2003, William G. Doherty Except where otherwise noted, this item's license is described as © 2003, William G. Doherty
This website uses cookies. By using this website, you consent to the use of cookies in accordance with the UCC Privacy and Cookies Statement. For more information about cookies and how you can disable them, visit our Privacy and Cookies statement