Critical heat anomaly in frustoelectric liquid crystals

Heat capacity of a liquid crystal which exhibits a frustoelectric phase has been measured by a high-resolution ac calorimeter. A significant heat capa city peak was observed at the transition. The excess heat capacity for this transition showed a non-landau critical behavior. The transition was found to be weakly first-order. The data have been analyzed with a preasymptotic power-law equation which includes correction-to-scaling terms.