Abstract
We use computer simulations to study the existence and stability of a biaxial nematic phase in systems of hard polyhedral cuboids, triangular prisms, and rhombic platelets, characterized by a long (), medium (), and short () particle axis. For all three shape families, we find stable states provided the shape is not only close to the so-called dual shape with but also sufficiently anisotropic with for rhombi, (two types of) triangular prisms, and cuboids, respectively, corresponding to anisotropies not considered before. Surprisingly, a direct isotropic- transition does not occur in these systems due to a destabilization of by a smectic (for cuboids and prisms) or a columnar (for platelets) phase at small or by an intervening uniaxial nematic phase at large . Our results are confirmed by a density functional theory provided the third virial coefficient is included and a continuous rather than a discrete (Zwanzig) set of particle orientations is taken into account.
- Received 26 January 2018
DOI:https://doi.org/10.1103/PhysRevLett.120.177801
© 2018 American Physical Society