Decomposition pathway of C4F7N gas considering the participation of ions.

Recently, fluoronitrile C₄F₇N is regarded as a promising alternative gas for SF₆, and its global warming potential (GWP) is extremely high. C₄F₇N has good insulation properties and a relatively low GWP, so it can be used as an insulation medium for gas-insulated switchgears. Some studies have been conducted on the decomposition pathway of C₄F₇N gas that may produce possible neutral molecules and free radicals, which helps understand the thermal decomposition of C₄F₇N. However, anions and cations will be produced under discharge conditions. In these cases, the decomposition pathway of C₄F₇N will be different. In this paper, the ionization decomposition pathway and the attachment decomposition pathway of C₄F₇N were first calculated, while the recombination processes of the cations and anions were also considered. The results can reveal the decomposition mechanism of C₄F₇N and the recombination mechanism of the stable products under discharge conditions. The energy changes of all the reactions were calculated, which reveals the difficulty of chemical reactions. To better investigate the formation mechanism of stable products, the partial discharge experiment was also carried out, and the decomposition products of C₄F₇N mixed gas were detected. Finally, the ionization energy and electron affinity energy of the stable products were also calculated, which can determine the difference in the total electronic energy between the neutral molecule and the ion. The results provide an important reference for studying the decomposition characteristics of C₄F₇N gas under discharge conditions from the theoretical aspect. [ABSTRACT FROM AUTHOR]