Rod-Like Liquid Crystals Combining RH- and RF-Chains Monolayer Smectic Phases

2 Rod-Like Liquid Crystals Combining RH- and RF-Chains Monolayer Smectic Phases 

there are two options for molecules with unlike end-chains either the incompatible chains mix which retains the lamellar structure, or these chains segregate and layer modulation with formation of ribbon phases (columnar phases) 

12 As the cross sectional area of the mixed RH and RF chains is still larger than that of the aromatic cores random tilt (de Vries-like SmA) or uniform tilt (SmC) can compensate this remaining mismatch. 

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