Molecular Orbitals in Conjugated Systems

This lecture covers the electronic structure of conjugated systems, focusing on frontier orbitals, bond orders, and Hückel theory. It explains the delocalization of π-electrons, the energy levels in linear and cyclic systems, and the HOMO-LUMO gap. The discussion extends to extended linear π-conjugated systems, resonance structures, and the effects of electron-donating and electron-withdrawing groups. The lecture also delves into the quadrupolar moment, electron density distribution, and intermolecular forces in conjugated molecules. Furthermore, it explores the packing patterns in electron-rich and electron-poor systems, emphasizing the equilibrium π-stacking structure. The session concludes with a study of mixed systems and their packing patterns, highlighting the learning outcomes related to the supramolecular organization and electron delocalization in the solid state.