PHASE-BEHAVIOR OF PARALLEL CUT SPHERES - MONTE-CARLO AND INTEGRAL-EQUATION RESULTS

Monte Carlo simulations of a system of 2500 parallel cut spheres of thickness L/D = 0.1 give evidence for a phase transition, at packing fraction eta approximately 0.40, from the low density nematic phase to a smectic phase. No tendency to formation of columnar ordering is observed up to densities as high as eta = 0.60. This behavior contrasts with that of freely rotating cut spheres for which the sequence of stable phases has been identified as isotropic-nematic-columnar-solid [D. Frenkel, Liquid Cryst. 5, 929 (1989)]. For the present system of highly anisotropic molecules the slow convergence of the expansion of correlation functions on rotational invariants precludes quantitative comparison between integral equation theory and simulation results.