Liquid crystalline phases are used in many everyday applications, such as display devices and household products, and their theoretical properties are of great interest. The virial series offers a sound theoretical approach for calculating the thermodynamic, structural and elastic properties of liquid and liquid crystalline phases. Many theories truncate the series at low order, but this can lead to inaccurate results and can miss the important phenomena. In this thesis, we use an eighth order virial expansion to calculate the equations of state of nematic liquid crystals, a~d the validity of the theory is determined by comparison to simulation results. We extend this theory to the novel cubatic liquid crystalline phase, a phase of matter for which little theoretical work exists. We use the extended theory to predict the stability of the phase, and again compare to simulation results to determine the validity of the theory. We also use the virial expansion to calculate structural properties of isotropic and nematic phases, including the direct correlation function and radial distribution function. We compare our theoretical results to those obtained from simulations, and test the accuracy of our theory against other theoretical predictions. These theories are then combined to calculate the elastic constants of nematic liquid crystals. The effects of confinement on liquid crystalline phases is explored using computer simulation. The phase behaviour and resultant frustration effects are reported. Bifurcation analysis is used to explore the effect of tethering polymer chains to nanorods. This approach.is then used to give a theoretical account as to why tethered particles should form liquid crystalline phases more readily than untethered particles. Molecular dynamics simulations are carried out on fused-sphere platelets, and the dynrurucal properties of the cubatic phase are explored using this system.
| Identifer | oai:union.ndltd.org:bl.uk/oai:ethos.bl.uk:505411 |
| Date | January 2009 |
| Creators | Dennison, Matthew |
| Publisher | University of Manchester |
| Source Sets | Ethos UK |
| Detected Language | English |
| Type | Electronic Thesis or Dissertation |
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