| Liquid crystal is a soft matter,a thermodynamically stable phase between liquid and crystalline,having both the mobility of liquid and the optical anisotropy of crystal.When the liquid crystals are confined within a specific physical space,the boundary’s existence has a significant impact on the system’s structure,and we call such a system a limited liquid crystals system.We systematically study the self-assembly behavior of liquid crystals under the elastic space constraint using a large-scale molecular dynamics simulation method accelerated by GPU(Graphics processing unit).Liquid crystals’ structure under various curved surfaces is studied by encapsulating them in a spherical elastic shell.It is worth stating that Lennard-Jones(LJ)particles stack the elastic spherical shells,and the positions are obtained by the triangular partitioning method,with six neighboring particles for each particle except for twelve particles with five neighboring particles at the location of the icosahedral vertices.Therefore,the spherical elastic shell’s deformation from soft to hard appears as a transition from an icosahedron to a perfect sphere.The liquid crystals are represented by uniaxial ellipsoidal particles Gay-Berne(GB,4.4,20,1,1)potential.By adjusting the bending energy constantly,elastic spherical shells with varying flexibility are obtained.The soft spherical shell deforms as the liquid crystals thermally expand,while in the hard spherical shell will not cause the spherical shell to deform.During cooling,only the Isotropic-Smectic-A phase transition is observed in the hard spherical shell confined system,while the phase behavior in the soft spherical shell confined system is consistent with the Isotropic-Nematic-Smectic-A phase transition in bulk.Compared to the hard spherical shell,the soft spherical shell arranges more orderly,and it makes the nematic phase temperature range wider and the structure clearer.So,adjusting the physical confined space boundary’s flexibility can control the liquid crystals’ response interval to the temperature.Simultaneously,our data results show that the higher the temperature,the smaller the spherical shell’s deformation and vice versa.The temperature causes the liquid crystal molecules to thermally expand in different arrangements,which leads to the final deformation of the elastic spherical shells.Combining the data in the article,we conclude that the ordered arrangement of liquid crystal and the flexible interface’s orientation effect is in a competitive relationship during the self-assembly process.Our results suggest that the phase behavior can be controlled by changing the confined boundaries’ flexibility,and it provides a new idea for the design of novel liquid crystal/polymer composite materials. |
