Progress in computer simulations of liquid crystals

This article reviews some of the recent progress in the simulation of liquid crystals across a range of length and time scales. Simulators now have an extensive range of models at their disposal, ranging from fully atomistic studies where each atom is represented in a simulation, via hard or soft anisotropic potentials, to lattice models and director-based simulation methods. Each of these provide access to different phenomena. The progress towards accurate atomistic modelling of nematics is discussed in detail, pointing to improvements in force fields made recently and discussing the progress towards accurate prediction of material properties. Three material properties are discussed in detail: elastic constants, rotational viscosity and helical twisting powers. The simulation methods that can be employed to extract such properties are reviewed and the insights provided by recent results from atomistic and coarse-grained models are discussed. The article points also to the recent success of coarse-grained modelling in helping to understand the structure of complex macromolecular liquid crystals: liquid crystal polymers and liquid crystal dendrimers in which the macromolecules contain different types of interaction site. Finally, it is worth noting that throughout Nature liquid crystals occur as the archetypal self-assembled materials; able to form well-defined self-organized structures, which are often ordered at the nanoscale. With this in mind, some perspectives on the future use of these materials are presented, with suggestions for how liquid crystal simulation can be used to help in the design of the next generation of nanoscale devices.