Influence of Molecular Structure and Aromaticity on the Arc Extinguish Performance of Perfluorinated Insulating Gases Under High Electric Field

Ultra-high voltage (UHV) power transmission has become a prerequisite for the development of clean energy. However, arcs generated by UHV circuit breakers can easily lead to safety incidents, and developing arc-extinguishing gases with low global warming potential (GWP) presents certain challenges. It is a fact that fluorolefins, as a class of fluorinated compounds with low GWP, show high application potential in replacing traditional arc-extinguishing agents. In this study, all six conjugated perfluorinated compounds, including C6F6 and C6F8, were calculated within the density functional theory (DFT) framework at the B3LYP/6-311+G(d,p) level. The dipole moments, HOMO/LUMO energy gaps, and the inherent aromaticity of annular molecules under external electric fields of these fluorinated molecules are investigated accordingly. By analyzing these results, it is found that the influence of the conjugated structure on the stability of arc-extinguishing gases under high-voltage conditions was partially elucidated, providing useful insights for the subsequent development of environmentally friendly and high-performance arc-extinguishing gases.