Cubatic structure

Mortensen, K Brown, W Norden, B, Inverse Melting Transition and Evidence of Three-Dimensional Cubatic Structure in a Block-Copolymer Micellar System, Physical Review Letters 68, 2340, 1992. 

Mortensen K, Brown W et al (1992) Inverse melting transition and evidence of three-dimensional cubatic structure in a block-copolymer micellar system. Phys Rev Lett 68 2340-2343... 

Particles bigger in diameter than the column can be incorporated with tilt. If a tilted particle occurs, it may be preferentially at the end of a stack where there is more space. This might favour the cubatic structure as shown schematically in Figure 4b rather than long columns. We have observed that the particles with different dimensions separate in different columns (not shown in the micrographs in the paper). In such case, whole columns with bigger particles are tilted to obtain a column width, W, that is smaller than D, the diameter of particle in the stack. One such example is shown schematically in Figure 4b. These different structures for a polydisperse... 

Abstract Self-assembly is an important phenomenon that leads to formation of interesting and novel structures in colloidal dispersions. We present experimental evidence for the existence of a cubatic phase in a colloidal dispersion of disc-like particles of nickel hydroxide colloidal dispersions. In this structure, disc-like particles self-assemble as domains of a few parallel discs and the orientation tends to be orthogonal in adjacent domains. This phase has been predicted previously by computer simulations. The domains are approximately equiaxial and are predicted to exist only within a limited range of aspect ratios and volume fractions. We have used the real space technique of cryo-transmission electron microscopy in our studies as this locally ordered structure could not be identified readily using scattering techniques, since the patterns are expected to be similar to those of isotropic liquid phases. 

A cryo-TEM image is shown in Figure 2 that indicates structures with cubatic order. 

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