In this work we perform a theoretical calculation in order to reconstitute the (E-T) phase diagram of a chiral smectic liquid crystal in the vicinity of the SmA-SmCα* transition. This reconstruction is carried out...In this work we perform a theoretical calculation in order to reconstitute the (E-T) phase diagram of a chiral smectic liquid crystal in the vicinity of the SmA-SmCα* transition. This reconstruction is carried out on the basis of a thermo-dynamic calculation of the slope of the curve joining the SmC* domain and the unwound SmC*. An empiric correction of the mean field term of Landau De-Gennes development is necessary to accomplish this reconstruction. Thereafter, an experimental validation is performed to verify our calculations.展开更多
Fluorinated smectic liquid crystals each with a biphenyl benzoate rigid core are investigated. Molecular structures of the studied compounds have difference only in fluorine position and the length of the carbon chain...Fluorinated smectic liquid crystals each with a biphenyl benzoate rigid core are investigated. Molecular structures of the studied compounds have difference only in fluorine position and the length of the carbon chain. Dielectric relaxation study and electro-optical measurements are carried out with the classical SSFLC geometry. The field-induced phase transitions are studied and the(E,T) phase diagram is established.展开更多
文摘In this work we perform a theoretical calculation in order to reconstitute the (E-T) phase diagram of a chiral smectic liquid crystal in the vicinity of the SmA-SmCα* transition. This reconstruction is carried out on the basis of a thermo-dynamic calculation of the slope of the curve joining the SmC* domain and the unwound SmC*. An empiric correction of the mean field term of Landau De-Gennes development is necessary to accomplish this reconstruction. Thereafter, an experimental validation is performed to verify our calculations.
文摘Fluorinated smectic liquid crystals each with a biphenyl benzoate rigid core are investigated. Molecular structures of the studied compounds have difference only in fluorine position and the length of the carbon chain. Dielectric relaxation study and electro-optical measurements are carried out with the classical SSFLC geometry. The field-induced phase transitions are studied and the(E,T) phase diagram is established.