Rational Design of Reliable Computational Protocols for Predicting Dielectric Constants of Gaseous Molecules

J Phys Chem A. 2024 Mar 21;128(11):2245-2252. doi: 10.1021/acs.jpca.3c08050. Epub 2024 Mar 12.

Abstract

A rapid prediction of the dielectric constants from a wide range of organic compounds is of paramount importance given the pressing need to find alternatives to SF6, one of the seven greenhouse gases. However, the availability of a universally applicable equation for predicting dielectric constants remains limited. This study endeavors to systematically develop a universal equation for predicting the dielectric constants of gaseous organic molecules in a systematic manner. The reliability of these newly developed equational protocols is evaluated through both quantitative (i.e., root-mean-squared deviation) and qualitative (i.e., Spearman's rank correlation coefficient) analyses. Equational optimization of the traditionally unreliable Clausius-Mossotti equation highlights the critical role of selecting a suitable variable to be incorporated into an adapted Clausius-Mossotti equation, ultimately enhancing the predictive accuracy. Furthermore, it is revealed that the nature of the chosen variable has a more significant impact on prediction accuracy than the quantity of variables introduced. These findings shed light on the ongoing efforts of developing a dependable protocol for predicting not only dielectric constants but also other vital insulating properties, such as dielectric strength.