Searching for nanostructures of the cubic mesophase of liquid crystal molecules, BABH8.
Nanostructures of a thermotropic cubic phase forming liquid crystal compound, 1,2-bis-[4-n-octyloxy-benzoyl]-hydrazine was studied by molecular dynamics (MD) simulations. A model for its cubic phase structure was proposed, which was constructed from the building unit of a locally orientational ordered "bundle" consistent with the cell parameter and the space group (Ia3d) from the recent x-ray results. Stability of the model structure was studied by multinanosecond MD simulations. A periodic nanostructure with 2.6 nm periodicity [coincides with the Ia3d (211) reflection] was kept up to 60 ns in the reduced pressure simulation which realizes the experimental value of density. However, the calculated fourth-rank order parameter shows that the simulated final state above does not have cubic orientational symmetry but rather isotropic symmetry.
Yokoyama Nano-structured Liquid Crystal Project, ERATO, Japan Science and Technology Agency, 5-9-9 Tokodai, Tsukuba 300-2635. yoneya@nanolc.jst.go.jp
Makoto
M
Yoneya
Etsushi
E
Nishikawa
Hiroshi
H
Yokoyama