Dissociative ionization dynamics of dielectric gas C3F7CN

0511868 - ÚFCH JH 2020 RIV GB eng J - Journal Article
Ranković, Miloš - Chalabala, J. - Zawadzki, Mateusz - Kočišek, Jaroslav - Slavíček, Petr - Fedor, Juraj
Dissociative ionization dynamics of dielectric gas C3F7CN.
Physical Chemistry Chemical Physics. Roč. 21, č. 30 (2019), s. 16451-16458. ISSN 1463-9076. E-ISSN 1463-9084
R&D Projects: GA TA ČR(CZ) TH03020063
Institutional support: RVO:61388955
Keywords : molecular-dynamics * nonadiabatic dynamics * mass-spectra * chemistry * replacement * mechanism * model * fock
OECD category: Physical chemistry
Impact factor: 3.430, year: 2019
Method of publishing: Limited access

Fluoronitrile C3F7CN is a promising candidate for the replacement of SF6 dielectric gas in high-voltage insulation. We present a combined experimental and theoretical study on its ionization dynamics probed in the 0-100 eV energy range. We exploited the total ion collection technique to determine the absolute ionization cross section, mass spectrometry to determine the fragment branching ratios and ab initio nonadiabatic molecular dynamics to simulate the ionization process. The latter two approaches showed the dominating presence of the CF3+ cation over the whole electron energy range. The Binary-Encounter-Bethe (BEB) approximation reproduces experimental cross sections very well and reveals that the ionization from a surprisingly large number of orbitals contributes almost equally to the processes. We show that the initially populated cation excited states undergo an ultrafast internal conversion to the ground state where the dissociation into a single decay channel takes place. Implications for the use of C3F7CN as an insulating material are discussed.
Permanent Link: http://hdl.handle.net/11104/0302115