Two-Particle Cluster Theory for Biaxial Nematic Phase Based ona Recently Proposed Interaction Potential

Abstract

Two-particle cluster theory is applied to study the biaxial nematicphase formed by biaxial molecules interacting with a simplified modelproposed by Sonnet et al. [Phys. Rev. E 67 (2003) 061701]. Forthe temperature dependences of the internal energy per particle and ofthe order parameters, the two-particle theory yields an improved resultcompared with mean field theory. Concerning the phase diagram, thetwo-particle theory gives the numerical result in qualitative agreementwith the mean field theory.