Exploring Elemental Sulfur‐Solvent Interactions via Density Functional Theory

Abstract

In order to further develop a comprehensive understanding of the weak interactions between elemental sulfur (S₈) and solvent molecules (carbon disulfide(CS₂), dimethyl disulfide(DMDS), dimethylformamide(DMF), dimethyl sulfoxide(DMSO)), we have investigated the intermolecular interactions between elemental sulfur and solvents based on density functional theory (DFT). Through electrostatic potential (ESP), frontier molecular orbitals (FMO), independent gradient model based on the hirshfeld (IGMH) analysis, atoms in molecules (AIM) topological analysis, and energy decomposition analysis (EDA), the results show that there are extensive van der Waals interactions between elemental sulfur and solvent molecules. IGMH method, AIM topological analysis and EDA results indicate that van der Waals dispersion attraction is a significant contributor to the total interaction energy of elemental sulfur with the solvent. The combination of various intermolecular non‐bonding forces determines the strength of the interaction between S₈ and the solvent. In addition, the difference in the interaction between solvent and elemental sulfur is mainly due to the unsaturated/polar functional group structure. Considering the structural properties of the S₈ molecule, avoiding substituents in the solvent molecule that have spatial site‐barrier and electron‐withdrawal effects is a feasible way to develop new efficient sulfur solvent systems.