title: Liquid-crystalline ordering as a concept in materials science: from semiconductors to stimuli-responsive devices.
abstract: While the unique optical properties of liquid crystals (LCs) are already well exploited for flat-panel displays, their intrinsic ability to self-organize into ordered mesophases, which are intermediate states between crystal and liquid, gives rise to a broad variety of additional applications. The high degree of molecular order, the possibility for large scale orientation, and the structural motif of the aromatic subunits recommend liquid-crystalline materials as organic semiconductors, which are solvent-processable and can easily be deposited on a substrate. The anisotropy of liquid crystals can further cause a stimuli-responsive macroscopic shape change of cross-linked polymer networks, which act as reversibly contracting artificial muscles. After illustrating the concept of liquid-crystalline order in this Review, emphasis will be placed on synthetic strategies for novel classes of LC materials, and the design and fabrication of active devices.
authors.affiliation: Institut für organische Chemie, Johannes Gutenberg-Universität Mainz, Duesbergweg 10-14, 55099 Mainz, Germany.
authors.forename: Eva-Kristina
authors.initials: EK
authors.lastname: Fleischmann
authors.forename: Rudolf
authors.initials: R
authors.lastname: Zentel
keywords: liquid crystals; materials chemistry; self-assembly; semiconductors