A theory of thermotropic nematic liquid crystals in which molecules form internally ordered clusters is presented. The formulation is based on the same molecular-field approximation and form of the anisotropic potential used in the Maier–Saupe theory. One uniaxial nematic and two macroscopically isotropic phases are predicted. The lower-temperature isotropic phase consists of thermodynamically stable clusters with internal orientational order. The transition from this phase to the nematic phase is characterised by the divergence of cluster size whilst the entropy and the order parameter change continuously.
Acknowledgements
Part of this research has been funded through the EU 7th Framework Programme (FP7/2007-2013) under the project BIND (Biaxial Nematic Devices, grant agreement #216025).