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A brief review and personal perspective of modelling and simulations of liquid crystals and of how this has dramatically changed over the years, from idealised lattice to molecular level and now to predictive atomistic models. [ABSTRACT FROM AUTHOR]

We have simulated, using a Monte Carlo method, a system of apolar Gay–Berne discotic particles without dipoles and with two or three dipoles symmetrically embedded in the disc. The dipoleless system can form nematic and hexagonal columnar mesophases. Adding two in‐plane antiparallel radial dipoles has the effect of destabilizing the columnar ordering, in favour of a fully interdigitated arrangement of the molecular stacks, with strong correlations in the plane perpendicular to the director and large biaxiality. No columnar phase is observed for the systems with three planar radial dipoles with threefold symmetry up to very low temperatures. Finally, on decreasing the strength of the three dipoles, a columnar non‐interdigitated phase is observed. [ABSTRACT FROM AUTHOR]

EPR spin probe spectra of the liquid crystal phases exhibited, in the bulk, by the 1",9"-bis(4- cyanobiphenyl-4'-yl)nonane (CB9CB) bent-shape dimer showed that, on cooling from the isotropic phase, this material forms a uniaxial nematic phase with a uniform director macroscopically aligned along the spectrometer field. Upon further cooling, a transition into the twist-bend nematic phase is observed after a biphasic region of approximately 4 K. In this lower temperature nematic phase, the director does not appear to be macroscopically aligned. The non-uniform director distribution is modelled as a collection of monodomains tilted with respect to the magnetic field and orientationally distributed around the tilt direction. [ABSTRACT FROM AUTHOR]

We study the charge transport properties of a system of liquid crystal discotic molecules in two distinct phases. To differentiate between the two phases, we use a self-consistent model that describes the pairwise interaction between molecules, the electronic coupling between them and the difference in orbital energies. This multi-scale approach hinges upon having systems that are both accurate (to within atomic resolution) and large (~10,000 molecules). The two phases have dramatically different charge transport network topologies, directly correlated to their molecular structures. We quantify the charge transport on both a macroscopic and microscopic scale, taking advantage of the model's resolution to understand the role of molecular packing in charge transport. [ABSTRACT FROM AUTHOR]

We have studied the alignment and molecular organisation within a thin film of the popular nematic 5CB sandwiched between two flat polymer slabs, examining the effect of polymer chemical nature and morphology with atomistic molecular dynamics simulations. We have chosen two common polymers: polystyrene (PS) and polymethylmethacrylate (PMMA), either with their chains in random coil conformation (disordered) or with chains unidirectionally stretched (ordered). We found that, independently on the arrangement of the chains, both surfaces align planarly the liquid crystal, in accord with experimental observation. Moreover, while 5CB molecules align along the chains stretching direction of the PMMA ordered surface, on the combed PS surface they arrange on average perpendicularly to the stretching direction. This behaviour is attributed to the chemically specific interactions between the respective aromatic moieties of PS and 5CB. [ABSTRACT FROM AUTHOR]