Structures and correlations in ideally aligned polar Gay-Berne systems

We study an ideally oriented system of Gay-Berne particles with embedded lo ngitudinal dipole moments. While keeping the translational degrees of freed om of the molecules unrestricted we assume that their dipoles can be orient ed either parallel or antiparallel to the positive z axis of the laboratory frame. At high temperatures, this frustrated Gay-Berne mesogen exhibits an ideally oriented nematic phase, which is the reference state of the system . In the limit of vanishing dipole moment nematic, smectic-A and smectic B phases are stable. Interestingly, by changing the magnitude and location of the molecular dipole in the nematic reference state we found dipole-induce d smectic A, smectic B and tetragonal crystal phases, in addition to crysta lline structures with smectic A(d) and A(2)-like dipolar organization. Vari ous singlet, pair and triplet distribution functions were evaluated to eluc idate short and long range organization in these phases. In particular, the importance of triplet correlations for a proper understanding of the struc tures and their local, dipolar organization is demonstrated.