The Insulation Strength Structure-Property Relationship Model of Gas Containing Double or Triple Bonds

In this article, the molecular structure of the insulating gas was optimized on the B3LYP Functional with DGDZVP Basis Settings based on density functional theory (DFT), the molecular descriptors of the sample gas were obtained, and a gas insulation strength data set containing 47 kinds of gas molecules was established. According to the gas discharge theory and the molecular descriptor screening method, four molecular descriptors that have a significant impact on the insulation strength were obtained. The multiple linear regression (MLR) method was used to establish the structure-property relationship model 1 between the gas molecule descriptors and the insulation strength. And on this basis, model 2 was established for gas molecules containing triple or double bonds, and the reliability and predictive ability of the model were significantly improved. The results show that the insulation strength of gas molecules is significantly related to van der Waals volume ( ${V}_{m}$ ), electrostatic potential positive ellipsoidized surface area ( ${A}_{\text {so}}^{+}$ ), highest occupied orbital energy ( ${E}_{\text {HOMO}}$ ), and lowest unoccupied orbital energy ( ${E}_{\text {LUMO}}$ ). When the molecular chemical bond type is considered, van der Waals surface area ( ${A}_{s}$ ) and positive and negative electrostatic potential balance parameters ( ${v}$ ) become the main factors affecting the strength of gas insulation.