Conformation Analysis of Environmentally Friendly Insulating Gas C5-PFK

The environmentally friendly insulating gas C5-PFK has the potential to replace SF6 in medium and low voltage gas insulated electrical equipment due to its good environmental performance and insulation strength. However, since C5-PFK molecule has rotatable C-C single bonds, the geometry will change when collided with each other or obtained external energy, which may have an impact on the stability and reactivity of C5-PFK molecule. In this paper, the geometry of C5-PFK molecule is optimized by the density functional theory-B3LYP-D3(BJ) method under the triple-zeta polarization basis set and high convergence criterion. The two C-C bonds connected with the carbonyl group (-C = O-) in C5-PFK molecule are rotated to scan its potential energy surface. Then, we obtained four possible conformers that might exist in C5-PFK molecule. The molecule structure, molecule energy, Mayer bond order, and energy levels (HOMO, LUMO orbital included) of frontier molecular orbital were analyzed to study the four conformers' stability and reactivity, which will pave the way for follow-up research work such as thermostability, transition state, reaction pathways, and adsorption behavior of C5-PFK.