Monte carlo study of Gay–Berne liquid-crystal droplets

Abstract

We report results of a series of NVT Monte Carol simulations on systems of molecules interacting via a Gay–Berne (GB) potential within a spherical cavity modelling a polymer-dispersed liquid-crystal (PDLC) droplet. The cavity walls have been simulated by constructing a spherical shell of GB particles, each oriented towards the centre of the drop in an attempt to promote radial boundary conditions. The wall–fluid interactions have been modelled with a modified 1–3 GB potential (with energy exponents µ-1 and ν= 3, respectively) to favour radial alignment. We show results for the molecular organization in the droplet for a 2–1 and 1–3 fluid–fluid potential. We also show the radial order parameter as a function of temperature and droplet size. It is found that at low scaled temperatures a layer of radially aligned particles is formed, but this ordering does not propagate towards the centre of the drop unless the drop is relatively large or all the fluid–fluid interactions are modelled with the 1–3 potential. In this situation, concentric shells of aligned particles are formed, with a small smectic-like domain in the centre.