Calculation of electric field-temperature (E, T) phase diagram of a ferroelectric liquid crystal near the SmA-SmC_α^* transition

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-SmC_α^* transition. This reconstruction is carried out on the basis of a thermodynamic calculation of the slope of the curve joining the SmC_α^* 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.