Chapter 4: Naphthalenediimide in Modular Columnar Liquid Crystals: Key Component of Donor–Acceptor Columnar Liquid Crystals

The development of new liquid crystalline (LC) materials has revolutionized many areas of science and technology. Discotic, or columnar liquid crystals (CLC), are a relatively new sub-class of LCs that have seen a surge of interest in the past three decades due to their potential to serve as organic semi-conducting materials. This chapter provides a brief introduction to LCs, and discusses the role of naphthalenediimide (NDI) derivatives in novel LC materials. In particular, NDI derivatives have played a key part in the development of a bi-component class of CLCs, termed donor–acceptor columnar liquid crystals (DACLCs). These supramolecular materials are formed from a combination of complementary electron-rich (donor) and electron-poor (acceptor) aromatic molecules, which can self-assembly to form mixed-stacked CLCs. Due to their modular nature, the unique properties of DACLCs can be tuned with relative ease, including phase transitions, stability, broad UV/Vis/NIR absorption characteristics, and promising optical and electronic properties. The history and current state of NDI-acceptor based DACLCs is discussed.