An adiabatic scanning calorimetry study of a chiral liquid crystal tolane with blue phases and twist grain boundary phases
作者： M Young , G Pitsi , M-H Li , H-T Nguyen , P Jamee
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摘要: High resolution adiabatic scanning calorimetry (ASC) was employed to study the phase behaviour exhibited by chiral liquid crystal material (R)-1-methylheptyl 3-fluoro-4- (3-fluoro-4-octadecyloxybenzoyloxy)tolane-4-carboxylate (FH/FH/HH-18BTMHC). We report on heat capacity of different phases and transitions as well enthalpy changes showing a sequence Cr-SmC*-TGBC-TGBA-BPI-BPIIBPIII-I. While presence BPI observed in previous DSC studies only cooling sample, our ASC measurements detected this also heating runs at sufficiently slow rates. Indications smectic order still present blue phases, recently reported from X-ray scattering experiments, are observed.
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