How Different are Electron-Rich and Electron-Deficient pi Interactions?

Abstract

The intermolecular interaction driven structural change is vital to molecular architecturing. In the Cambridge Structural Database (CSD), we find that the preference for geometrical conformations of electron-deficient pi systems is different from those of electron-rich pi systems. Indeed, ab initio calculations find that electron-deficient pi ring systems should involve different structures and energetics, consistent with the CSD search, due to the electric multipole moments and the decrease in the spatial extent of pi-electron density.