A frustrated packing model for the B6-B1-SmAPA sequence of phases in banana shaped molecules
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A vast majority of compounds with bent core or banana shaped molecules exhibit the phase sequence B6-B1-B2 as the chain length is increased in a homologous series. The B6 phase has an intercalated fluid lamellar structure with a layer spacing of half the molecular length. The B1 phase has a two dimensionally periodic rectangular columnar structure. The B2 phase has a monolayer fluid lamellar structure with molecules tilted with respect to the layer normal. Neglecting the tilt order of the molecules in the B2 phase, we have developed a frustrated packing model to describe this phase sequence qualitatively. The model has some analogy with that of the frustrated smectics exhibited by highly polar rod like molecules.
KeywordsPolymer Physical Chemistry Neural Network Thin Film Complex System
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