Reply to “Comment on ‘Origin of tilted-phase generation in systems of ellipsoidal molecules with dipolar interactions’ ”

In a recent article [T. K. Bose and J. Saha, Phys. Rev. E 86, 050701 (2012)], we have presented the results of a Monte Carlo simulation study of the systems of dipolar Gay-Berne ellipsoids where two terminal antiparallel dipoles are placed symmetrically on the long axis of each ellipsoid, and the results revealed the combined contribution of dipolar separation and transverse orientations in controlling the tilt angle in the tilted hexatic smectic phase. The tilt angle changed from zero to a significant value, in the case of transverse dipoles, with a change in the dipolar separation. In the related comment, Madhusudana [preceding Comment, Phys. Rev. E 89, 046501 (2014)] has claimed that the physical origin of the molecular tilt in the significantly tilted phases found in the simulations is similar to that proposed by McMillan [Phys. Rev. A 8, 1921 (1973)]. Here, we explain that the claim is not correct and make it clear that the two compared pictures are quite different. In the preceding Comment, Madhusudana has also suggested an alternative explanation for tilt generation in the simulations by criticizing the original one proposed by us. We argue here in support of the original explanation and clarify that his explanation does not follow the simulation results.

Figure 1

(a) McMillan model for the smectic-C phase where the outboard dipoles, represented by the arrows, are all oriented such that the dipolar layers become polarized with the polarization vector lying in the tilt plane. (b) A snapshot of the dipolar arrangement in the tilted hexatic smectic phase obtained for $(\kappa =5,d=4{\sigma }_0)$ where the short red ellipsoids are representing the dipolar orientations and the long green ellipsoids are representing the ellipsoidal particles. It can be seen that most of the embedded red ellipsoids are oriented approximately in a direction perpendicular to the tilt plane, in contrast to the dipolar arrangement shown in (a), where the dipoles lie on a tilt plane. (c) Dipolar arrangement in two neighbouring dipolar layers of two different molecular layers with extra added separation in order to properly see their dipolar orientations as the dipolar layers are likely to interpenetrate, as shown in (b). The snapshots were generated using the graphics software qmga [3].