BACK Liquid crystals comprise a large number of fascinating states of soft condensed matter where the orientational order of the constituent molecules is associated with a reduced or absent translational order. This combination of properties confers on liquid crystalline systems a combination of fluidity and easy alignment in external fields as well as anisotropic properties, similar to those of a crystal, that are the basis of their many technological applications in displays or other electro-optical devices.
An understanding of the macroscopic properties of liquid crystals and of their phase transitions in terms of molecular models can only be attained using computer simulations, possibly with the complement of approximate statistical mechanical theories. Computer simulations are particularly interesting and timely now because of their very rapid development and wide reach. While simulations of liquid crystals are of course based on the same general Monte Carlo and Molecular Dynamics techniques used for other fluids, they present a number of problems and peculiarities connected with the intrinsic properties of liquid crystals such as their long-range order and their anisotropy, that recommend a separate treatment. This requires in turn the development of suitable algorithms to calculate static properties such as order parameters, correlation functions, elastic constants and in general tensorial observables as well as dynamic quantities such as diffusion tensors, viscosities, susceptivities etc. It is now also becoming possible to examine topological defects characteristic of the various liquid crystals and to investigate their core structure and even to perform direct microscopic level simulations of simple devices and displays. Another series of problems is connected to the need of predicting the properties of liquid crystals from molecular models. This involves the determination of phase behaviour, phase transitions and their characteristics, and requires the developing of intermolecular potentials for modeling the essential molecular features of mesogens, and performing large scale simulations, with a number of particles often an order of magnitude greater than those used in simple fluid simulations. This in turn requires exploiting state of the art resources in computing, and particularly parallel computing techniques with the development of appropriate algorithms.
This School aims to provide an up to date coverage of all the issues above considering the various techniques, model systems (from lattice to hard particle and Gay-Berne up to atomistic) for thermotropics, lyotropics and some liquid crystals of biological interest. We are bringing together a number of top specialists in the field that will lecture on topics that in many cases they have themselves pioneered, providing young postdoctoral students with a clear first hand view of the field and of the different approaches. The format of the lectures will be the usual one for an ASI, while some specific topics will be covered by contributed papers in one afternoon. All participants will also have the opportunity to present their recent work in poster sessions in the evening. Ample time for discussions and informal meeting should lead to new contacts and collaborations. The present state and perspectives of the field will be reviewed in a panel discussion at the end of the meeting.