Molecular design and computer simulations of novel mesophases

The simulation of systems of simple particles interacting through a suitable model potential allows the identification of the essential physical features (anisotropy and biaxiality, electrostatic moments etc.) responsible for a certain collective behaviour. Here attractive–repulsive models of the so called Gay–Berne type, that have proved capable of generating nematic, smectic and columnar liquid crystals are described. In particular we discuss the generalization of this simple potential needed to handle biaxial and non-centrosymmetric molecules and we show that by suitable tuning of attractive and repulsive interactions biaxial and polar ferroelectric nematic phases can be obtained in simulations. This could hopefully offer a guide for the design of new mesogenic molecules that are reasonable candidates for the synthesis of these novel mesophases.

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