Crystal Packing of Conjugated Molecules

This lecture covers the shapes and crystal structures of r-conjugated molecules, including calamitic and discotic molecules, as well as the basic crystal structure types of A-conjugated hydrocarbons. It discusses packing arguments, polymorphism, and specific examples like benzene, pentacene, and coronene. The lecture also explores the crystal structures of various conjugated molecules, such as hexaphenylene, a-quaterthiophene, and BTBT, highlighting their packing arrangements and interactions. Additionally, it delves into the impact of substituents on crystal packing, phase segregation effects, and the formation of liquid-crystalline phases. The learning outcomes emphasize the balance between quadrupolar moment and dispersive forces in crystal packing, the preference for specific packing structures based on molecule size, and the importance of efficient packing for device applications.