Influence of Alkoxy Groups on the Photoinduced Dynamics of Organic Molecules Exemplified on Alkyl Vinyl Ethers
2015 (English)In: Journal of Physical Chemistry A, ISSN 1089-5639, E-ISSN 1520-5215, Vol. 119, no 45, 11105-11112 p.Article in journal (Refereed) Published
A series of different alkyl vinyl ethers is investigated to decipher the possible reaction channels upon photoexcitation to the pi 3s-Rydberg and the pi pi*-valence state at 200 nm using time-resolved photoelectron spectroscopy and on-the-fly time-dependent density functional theory dynamics simulations. The results indicate two possible relaxation pathways: (1) a radiationless decay through the pi pi*-state back to the ground state via torsion of the C=C double bond, in accordance with the dynamics found in ethylene; and (2) a fast dissociation of the C-O bond between the alkyl and the vinoxy group in the pi sigma*-state. The latter state can be accessed only after excitation to the pi 3s-Rydberg state (quantum yield of similar to 50% according to the dynamics simulations). Additionally, the excited state barrier leading to formation of a vinyl radical was found to be too high to be crossed. These results indicate that the dynamics of ethers crucially depend on the excitation wavelength and that the pi sigma*-state constitutes an important competitive reaction channel that leads to dissociation of the molecules.
Place, publisher, year, edition, pages
2015. Vol. 119, no 45, 11105-11112 p.
IdentifiersURN: urn:nbn:se:uu:diva-268397DOI: 10.1021/acs.jpca.5b06592ISI: 000364435300008PubMedID: 26490385OAI: oai:DiVA.org:uu-268397DiVA: diva2:878544
FunderSwedish Research CouncilKnut and Alice Wallenberg FoundationGöran Gustafsson Foundation for promotion of scientific research at Uppala University and Royal Institute of TechnologyWenner-Gren FoundationseSSENCE - An eScience Collaboration