The Bifurcated σ-Hole•••σ-Hole Stacking Interactions

The bifurcated sigma-hole & BULL;& BULL;& BULL;sigma-hole stacking interactions between organosulfur molecules, which are key components of organic optical and electronic materials, were investigated by using a combined method of the Cambridge Structural Database search and quantum chemical calculation. Due to the geometric constraints, the binding energy of one bifurcated sigma-hole & BULL;& BULL;& BULL;sigma-hole stacking interaction is in general smaller than the sum of the binding energies of two free monofurcated sigma-hole & BULL;& BULL;& BULL;sigma-hole stacking interactions. The bifurcated sigma-hole & BULL;& BULL;& BULL;sigma-hole stacking interactions are still of the dispersion-dominated noncovalent interactions. However, in contrast to the linear monofurcated sigma-hole & BULL;& BULL;& BULL;sigma-hole stacking interaction, the contribution of the electrostatic energy to the total attractive interaction energy increases significantly and the dispersion component of the total attractive interaction energy decreases significantly for the bifurcated sigma-hole & BULL;& BULL;& BULL;sigma-hole stacking interaction. Another important finding of this study is that the low-cost spin-component scaled zeroth-order symmetry-adapted perturbation theory performs perfectly in the study of the bifurcated sigma-hole & BULL;& BULL;& BULL;sigma-hole stacking interactions. This work will provide valuable information for the design and synthesis of novel organic optical and electronic materials.

Automated summary

In this study, the bifurcated sigma-hole and sigma-hole stacking interactions between organosulfur molecules were investigated using a combined method of the Cambridge Structural Database search and quantum chemical calculation. It was found that the binding energy of the bifurcated sigma-hole stacking interaction is generally lower than the sum of the binding energies of two monofurcated sigma-hole stacking interactions. The electrostatic energy contribution increases significantly and the dispersion component decreases significantly for the bifurcated sigma-hole stacking interaction compared to the linear monofurcated sigma-hole stacking interaction. Another important finding is that the spin-component scaled zeroth-order symmetry-adapted perturbation theory performs well in studying the bifurcated sigma-hole stacking interactions. This work provides valuable information for the design and synthesis of novel organic optical and electronic materials.