dc.contributor.author | Davari, Nazanin | |
dc.contributor.author | Åstrand, Per-Olof | |
dc.contributor.author | Unge, Mikael | |
dc.contributor.author | Lundgaard, Lars Esben | |
dc.contributor.author | Linhjell, Dag | |
dc.date.accessioned | 2015-09-21T13:21:43Z | |
dc.date.accessioned | 2016-04-12T14:17:27Z | |
dc.date.available | 2015-09-21T13:21:43Z | |
dc.date.available | 2016-04-12T14:17:27Z | |
dc.date.issued | 2014 | |
dc.identifier.citation | AIP Advances 2014, 4(3) | nb_NO |
dc.identifier.issn | 2158-3226 | |
dc.identifier.uri | http://hdl.handle.net/11250/2385347 | |
dc.description.abstract | Themolecular ionization potential has a relatively strong electric-field dependence as
compared to the excitation energies which has implications for electrical insulation
since the excited states work as an energy sink emitting light in the UV/VIS region.
At some threshold field, all the excited states of the molecule have vanished and
the molecule is a two-state system with the ground state and the ionized state,
which has been hypothesized as a possible origin of different streamer propagation
modes. Constrained density-functional theory is used to calculate the field-dependent
ionization potential of different types of molecules relevant for electrically insulating
liquids. The low singlet-singlet excitation energies of each molecule have also been
calculated using time-dependent density functional theory. It is shown that low-energy
singlet-singlet excitation of the type n→π* (lone pair to unoccupied π* orbital) has
the ability to survive at higher fields. This type of excitation can for example be found
in esters, diketones and many color dyes. For alkanes (as for example n-tridecane
and cyclohexane) on the other hand, all the excited states, in particular the σ →σ*
excitations vanish in electric fields higher than 10 MV/cm. Further implications for the
design of electrically insulating dielectric liquids based on the molecular ionization
potential and excitation energies are discussed. | nb_NO |
dc.language.iso | eng | nb_NO |
dc.publisher | American Institute of Physics | nb_NO |
dc.rights | Navngivelse 3.0 Norge | * |
dc.rights.uri | http://creativecommons.org/licenses/by/3.0/no/ | * |
dc.title | Field-dependent molecular ionization and excitation energies: Implications for electrically insulating liquids | nb_NO |
dc.type | Journal article | nb_NO |
dc.type | Peer reviewed | nb_NO |
dc.date.updated | 2015-09-21T13:21:43Z | |
dc.source.volume | 4 | nb_NO |
dc.source.journal | AIP Advances | nb_NO |
dc.source.issue | 3 | nb_NO |
dc.identifier.doi | 10.1063/1.4869311 | |
dc.identifier.cristin | 1123654 | |
dc.description.localcode | (c) 2014 Author(s). All article content, except where otherwise noted, is licensed under a Creative Commons Attribution 3.0 Unported License. | nb_NO |